WORLD WIDE WEB FREQUENTLY ASKED QUESTIONS 1995
[Note: Both parts of this FAQ have been combined into one file for this
archive.]
Archive-name: www/faq/part1
Last-modified: 1995/26/1
WORLD WIDE WEB FREQUENTLY ASKED QUESTIONS
This is part 1 of a 2-part posting.
Part 2 begins with section 5 (providing
information to the web). It should be the next
posting in this thread.
This document resides on the World Wide Web on Sunsite (URL is
http://sunsite.unc.edu/boutell/faq/www_faq.html ).
If you are unfamiliar with the term "URL", read on and learn!
Last update: 1/26/95
Contents
* 1: Recent changes to the FAQ
* 2: Information about this document
* 3: Elementary Questions
+ 3.1: What are WWW, hypertext and hypermedia?
+ 3.2: What is a URL?
+ 3.3: What are SGML and HTML?
+ 3.4: How does WWW compare to gopher and WAIS?
+ 3.5: Are there books about the web?
* 4: Accessing the Web (User Questions)
+ 4.1: Introduction: How can I access the web? (Even by email!)
+ 4.2: Browsers Accessible by Telnet
+ 4.3: Obtaining browsers
o 4.3.1: MS Windows, IBM OS/2 and MS Windows NT browsers
o 4.3.2: MSDOS browsers
o 4.3.3: Macintosh browsers
o 4.3.4: Amiga browsers
o 4.3.5: NeXTStep browsers
o 4.3.6: X/DecWindows (graphical UNIX, VMS) browsers
o 4.3.7: Text-based Unix and VMS browsers
o 4.3.8: VM/CMS browsers
o 4.3.9: Batch-mode "browsers"
+ 4.4: How can I access the web through a firewall?
+ 4.5: What is on the web?
o 4.5.1: How do I find out what's new on the web?
o 4.5.2: Where is the subject catalog of the web?
o 4.5.3: How can I search through ALL web sites?
+ 4.6: How can I save an inline image to disk?
+ 4.7: How can I get sound from the PC speaker with WinMosaic?
+ 4.8: I have a Windows PC (or a Macintosh). Why can't I open
WAIS URLs?
+ 4.9: I'm running XMosaic. Why can't I get external viewers
working?
+ 4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?
+ 4.11: How do I send newsgroup posts in HTML to my web client?
+ 4.12: I can't get SLIP. I want Mosaic. Is there a way? (YES!)
* 5: Providing Information to the Web (Provider Questions)
+ 5.1: How can I provide information to the web?
+ 5.2: Obtaining Servers
o 5.2.1: Unix Servers
o 5.2.2: Macintosh Servers
o 5.2.3: MS Windows, IBM OS/2 and MS Windows NT Servers
o 5.2.4: MSDOS and Novell Netware Servers
o 5.2.5: VMS Servers
o 5.2.6: Amiga Servers
o 5.2.7: VM/CMS Servers
o 5.2.8: Yeah, but which is best?
+ 5.3: Producing HTML documents
o 5.3.1: Writing HTML directly
o 5.3.2: HTML editors
o 5.3.3: Converting other formats to HTML
o 5.3.4: Checking your HTML for errors
+ 5.4: How do I publicize my work?
+ 5.5: Can I buy space on an existing server?
+ 5.6: How fast does my net connection have to be?
+ 5.7: Advanced Provider Questions
o 5.7.1: How do I set up a clickable image map?
o 5.7.2: How do I make a "link" that doesn't load a new
page?
o 5.7.3: Where can I learn how to create fill-out forms?
# 5.7.3.1: How can I create hidden fields in forms
(keeping state)?
# 5.7.3.2: How can users email me through their
browsers?
o 5.7.4: How do I comment an HTML document?
o 5.7.5: How can I create decent-looking tables and stop
using <PRE>...</PRE>?
o 5.7.6: What is HTML Level 3 and where can I learn more
about it?
o 5.7.7: How can I make interlaced and transparent GIFs?
And what are they?
o 5.7.8: How come mailto: URLs don't work?
o 5.7.9: How can I restrict and control access to my
server?
o 5.7.10: Which format is better for WWW images, JPEG or
GIF?
o 5.7.11: How can I mirror part of another server?
o 5.7.12: How can I keep robots off my server?
o 5.7.13: How can I keep statistics about my web site?
o 5.7.14: How can I generate web pages on the fly from a
program?
# 5.7.14.1: How can I generate GIF images on the fly
from my CGI programs?
* 6: Where can I discuss the Web?
+ 6.1: USENET Newsgroups
+ 6.2: Mailing Lists
* 7: I want to know more.
* 8: Credits
1: RECENT ADDITIONS AND CHANGES TO THE FAQ
* Added htmlchek to validation section
* Added information on interlaced GIFs
* Added information on the WN Server
* Added information on CGI script authoring
* Added information on the gd GIF-generating library
* Updated email links section
* More books!
* Slipknot section updated
* GLACI-HTTPD, a WWW server for Novell Netware
* WWW mailing lists section
* Updated URL for Gabriel White's HTML editor reviews
* IBM OS/2 WebExplorer
* MapMaker: From xv's Visual Schnauzer to an imagemap
* Added comp.infosystems.www.announce
* Added the Arena browser
2: INFORMATION ABOUT THIS DOCUMENT
This is an introduction to the World Wide Web project, describing the
concepts, software and access methods. It is aimed at people who know
a little about navigating the Internet, but want to know more about
WWW specifically. If you don't think you are up to this level, try an
introductory Internet book such as Ed Krol's "The Whole Internet" or
"EFF's Guide to the Internet". The latter is available electronically
by anonymous FTP from ftp.eff.org in the directory
pub/Net_info/EFF_Net_Guide.
This informational document is posted to news.answers,
comp.infosystems.www.users, comp.infosystems.www.providers,
comp.infosystems.www.announce, comp.infosystems.www.misc,
comp.infosystems.gopher, comp.infosystems.wais and alt.hypertext every
four days (please allow a day or two for it to propagate to your
site). The latest and best version is always available on the web as
http://sunsite.unc.edu/boutell/faq/www_faq.html , and is mirrored in
Japan (URL is
http://www.glocom.ac.jp/mirror/sunsite.unc.edu/boutell/faq/www_faq.htm
l ). (see section 3.2, "What is a URL?" to understand what this term
means.) If you run a mirror site which automatically mirrors this
document, please submit the URL for inclusion in the list of mirrors.
Thanks to both Sunsite and Glocom.
This document is also available by anonymous FTP from ftp.netcom.com
in the directory pub/bo/boutell/faq.
In addition, the most recently posted version of this document is kept
on the news.answers archive on rtfm.mit.edu in
/pub/usenet/news.answers/www/faq. For information on FTP, send e-mail
to mail-server@rtfm.mit.edu with:
send usenet/news.answers/finding-sources
in the body (not subject line) of your message, instead of asking me.
If you want the HTML version but are located behind a firewall, you
can acquire it from CERN's WWW email server. Send mail to
listproc@www0.cern.ch with the following single line in the body
(leave the subject blank):
source http://sunsite.unc.edu/boutell/faq/www_faq.html
Thomas Boutell maintains this document. Feedback about it is to be
sent via e-mail to boutell@netcom.com.
In all cases, regard this document as out of date. Definitive
information should be on the web, and static versions such as this
should be considered unreliable at best. The most up-to-date version
of the FAQ is the version maintained on the web. Please excuse any
formatting inconsistencies in the posted version of this document, as
it is automatically generated from the on-line version.
3: ELEMENTARY QUESTIONS
3.1: What are WWW, hypertext and hypermedia?
WWW stands for "World Wide Web". The WWW project, started by CERN (the
European Laboratory for Particle Physics), seeks to build a
distributed hypermedia system.
The advantage of hypertext is that in a hypertext document, if you
want more information about a particular subject mentioned, you can
usually "just click on it" to read further detail. In fact, documents
can be and often are linked to other documents by completely different
authors -- much like footnoting, but you can get the referenced
document instantly!
To access the web, you run a browser program. The browser reads
documents, and can fetch documents from other sources. Information
providers set up hypermedia servers which browsers can get documents
from.
The browsers can, in addition, access files by FTP, NNTP (the Internet
news protocol), gopher and an ever-increasing range of other methods.
On top of these, if the server has search capabilities, the browsers
will permit searches of documents and databases.
The documents that the browsers display are hypertext documents.
Hypertext is text with pointers to other text. The browsers let you
deal with the pointers in a transparent way -- select the pointer, and
you are presented with the text that is pointed to.
Hypermedia is a superset of hypertext -- it is any medium with
pointers to other media. This means that browsers might not display a
text file, but might display images or sound or animations.
3.2: What is a URL?
URL stands for "Uniform Resource Locator". It is a draft standard for
specifying an object on the Internet, such as a file or newsgroup.
URLs look like this: (file: and ftp: URLs are synonymous.)
* file://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip
* ftp://wuarchive.wustl.edu/mirrors
* http://info.cern.ch:80/default.html
* news:alt.hypertext
* telnet://dra.com
The first part of the URL, before the colon, specifies the access
method. The part of the URL after the colon is interpreted specific to
the access method. In general, two slashes after the colon indicate a
machine name (machine:port is also valid).
When you are told to "check out this URL", what to do next depends on
your browser; please check the help for your particular browser. For
the line-mode browser at CERN, which you will quite possibly use first
via telnet, the command to try a URL is "GO URL" (substitute the
actual URL of course). In Lynx you just select the "GO" link on the
first page you see; in graphical browsers, there's usually an "Open
URL" option in the menus.
3.3: What are SGML and HTML?
Documents on the World Wide Web are written in a simple "markup
language" called HTML, which stands for Hypertext Markup Language. See
section 5.3 for more information about creating HTML documents for use
on the web.
SGML is a much broader language which is used to define particular
markup languages for particular purposes. HTML is just a specific
application of SGML. You can learn more about SGML, and the rationale
behind HTML, by reading A Gentle Introduction to SGML (URL is
http://etext.virginia.edu/bin/tei-tocs?div=DIV1%26id=SG ), a document
provided by the Text Encoding Initiative. (Note: Some browsers
apparently crash on this URL. There's nothing wrong with the document;
try another browser if you have problems.)
3.4: How does WWW compare to gopher and WAIS?
While all three of these information presentation systems are
client-server based, they differ in terms of their model of data. In
gopher, data is either a menu, a document, an index or a telnet
connection. In WAIS, everything is an index and everything that is
returned from the index is a document. In WWW, everything is a
(possibly) hypertext document which may be searchable.
In practice, this means that WWW can represent the gopher (a menu is a
list of links, a gopher document is a hypertext document without
links, searches are the same, telnet sessions are the same) and WAIS
(a WAIS index is a searchable page, returning a document with no
links) data models as well as providing extra functionality.
World Wide Web usage grew far beyond Gopher usage in the last few
months, according to the statistics-keepers of the Internet backbone.
(Of course, World Wide Web browsers can also access Gopher servers,
which inflates the numbers for the latter.) WWW has long since reached
critical mass, with new commercial and noncommercial sites appearing
daily.
3.5: Are there books about the web?
Yes, quite a few. A brief list follows. New entries are solicited.
Please include ISBN numbers and/or ordering information.
The Mosaic Handbook (Mac, Windows and X editions)
From O'Reilly. A short, sweet guide to the World Wide Web from
a Mosaic user's perspective. Mac and Windows versions Include
Enhanced NCSA Mosaic on floppy disk; the X Window System
version includes NCSA Mosaic on CD-ROM. Telnet or gopher to
gopher.ora.com (log in as gopher) or find details on the web
(URL is http://gnn.com/ora/ ). Wherever fine X Window System
books and Nutshell Guides are sold.
The World Wide Web Unleashed
From Sams Publishing. By John December and Neil Randall.
Additional chapters contributed by others; I wrote the chapter
on HTML editors and filters. Covers both user and provider
issues in detail. Supporting pages available on the web (URL is
http://www.rpi.edu/~decemj/works/wwwu.html ). 1057 pages. ISBN:
0-672-30617-4. Call 1-800-428-5331 or +1-317-581-3500 for
ordering information.
Spinning the Web: How to Provide Information on the Internet
From Van Nostrand Reinhold. By Andrew Ford. Oriented toward
those with an interest in putting their data on the web. ISBN:
1-850-32141-8 (New York), 0-442-01962-9 (London). Available in
December 1994.
Teach Yourself Web Publishing with HTML in a Week
From Sams Publishing. By Laura Lemay. Also oriented toward
those who plan to publish materials on the web. ISBN:
0-672-30667-0. 400 pages. Includes information on setting up
servers and handling forms results as well as HTML writing and
editing. (URL is: http://slack.lne.com/lemay/theBook/index.html
) Available December 22nd, 1994. Call 1-800-428-5331 or
+1-317-581-3500 for ordering information.
The HTML Manual of Style
From Ziff-Davis Press. By Larry Aronson. Chapters: introduction
to the WWW, the HTML language, writing HTML documents, and HTML
examples. 120 pages. Available in December 1994.
The Internet via Mosaic and World-Wide Web
From Ziff-Davis Press. By Steve Browne. Details on obtaining
Mosaic and Trumpet Winsock, getting it all set up, and what to
do with it once it works. A chapter of interesting sites on the
Web as well. ISBN: 1-56276-259-1.
MOSAIC Quick Tour
From Ventana Press. By Gareth Branwyn. A good guide to
installing and using NCSA Mosaic under Windows. Includes basic
HTML and trouble-shooting chapters. "More hand-holding than the
FAQ and gives lots of details." - Mari J. Stoddard
Managing Internet Information Services
From O'Reilly and Associates. By Cricket Liu, Jerry Peek, Russ
Jones, Bryan Buus & Adrian Nye. A good choice for those who
will be installing and maintaining WWW servers; also includes
documentation on HTML, imagemaps and the like. Also covers
other types of Internet services.
Hands-On Mosaic: A Guide for Window Users
From Prentice Hall. By Dr. David Sachs & Henry Stair. ISBN:
0-13-172321-9.
HTML Authoring for Fun & Profit
From Prentice Hall. By Mary Morris. Jan 1995. ISBN:
0-13-359290-1.
NCSA Mosaic Handbook
From Prentice Hall. By Amy K. Kreiling & Frank Baker. Jan 1995.
ISBN: 0-13-196692-8.
Plug-n-Play Mosaic for Windows
From Sams. By Angela Gunn. ISBN 0-672-30627-1. 300 pages. Disks
include a special version of Enhanced NCSA Mosaic for Windows
with built-in TCP/IP Winsock and dialer, and an automated
configuration program (hence "plug-n-play"). The book is an
introduction to Mosaic and the Web with some coverage of
creating a home page and HTML and, of course, the obligatory
directory of Web sites.
Using Mosaic
From Que. Ed. by Que Development Group. ISBN: 0-7897-0021-2.
Covers NCSA Mosaic for Windows and the Macintosh.
Using the World Wide Web
From Que. Ed. by Que Development Group. ISBN: 0-7897-0016-6.
Mosaic User's Guide
From MIS Press. By Bryan Pfaffenberger. ISBN: 1-55828-409-5.
Using Mosaic for Windows
From Electric Avenue Press. By Stephen Gauer. ISBN:
0-969-8853-0-X.
4.1: Introduction: how can I access the web?
You have three options: use a browser on your own machine (the best
option), use a browser that can be telnetted to (not as good), or
access the web by email (the least attractive, but for some it's the
only way). It is always best to run a browser on your own machine,
unless you absolutely cannot do so; but feel free to telnet to a
browser for your first look at the web, or use email if the telnet
command does not work on your system (try it first!). Note that
"your machine" can be defined as a system you dial into from home,
such as netcom or another account provider. Running a text-based
browser on such a system is still preferable to telnetting to a
faraway site.
The following sections cover telnetting to a browser and obtaining
your own browser; if neither of these are possible for you (because
you have only an email-and-news connection to the Internet), here is
how to access a web page by email:
Send email to server@mail.w3.org (preferred) or to
listserv@info.cern.ch (older address if the first fails) containing
the following single line. (What you put on the subject line doesn't
matter; blank is OK. This line should go in the text of the message.)
You will receive as a reply a simple page intended to help you learn
more about the Web.
send http://www.earn.net/gnrt/www.html
4.2: Browsers accessible by telnet
An up-to-date list of these is available on the Web as
http://info.cern.ch/hypertext/WWW/FAQ/Bootstrap.html and should be
regarded as an authoritative list.
telnet.w3.org
A telnettable browser provided by the W3 coalition.
www.cc.ukans.edu
Offers Lynx, a full screen browser which requires a vt100
terminal. Log in as www. Does not allow users to "go" to
arbitrary URLs, so GET YOUR OWN COPY of Lynx and install it on
your system if your administrator has not done so already. The
best plain-text browser, so move mountains if necessary to get
your own copy of Lynx!
www.njit.edu
(or telnet 128.235.163.2) Log in as www. A full-screen browser
in New Jersey Institute of Technology. USA.
www.huji.ac.il
A dual-language Hebrew/English database, with links to the rest
of the world. The line mode browser, plus extra features. Log
in as www. Hebrew University of Jerusalem, Israel.
sun.uakom.cs
Slovakia. Has a slow link, only use from nearby.
info.funet.fi
(or telnet 128.214.6.102). Log in as www. Offers several
browsers, including Lynx (goto option is disabled there also).
fserv.kfki.hu
Hungary. Has slow link, use from nearby. Login is as www.
4.3: Obtaining browsers
The preferred method of access of the Web is to run a browser
yourself. Browsers are available for many platforms, both in source
and executable forms. Here is a list generated from the authoritative
list, http://info.cern.ch/hypertext/WWW/Clients.html .
4.3.1: MICROSOFT WINDOWS BROWSERS
NOTE: Most of these browsers require that you have SLIP, PPP or other
TCP/IP networking on your PC. The sole exception is SlipKnot, which
has limited features but operates well without a proper Internet
connection. SLIP or PPP can be accomplished over phone lines. You can
do this one of two ways: using a proper SLIP account, which requires
the active cooperation of your network provider or educational
institution, or using The Internet Adapter (section 4.12), a product
which simulates SLIP through your dialup Unix shell account. If you
only have non-Unix based dialup shell access, or have no PC at home,
your best option at this time is to run Lynx on the VMS (or Unix,
or...) system you call, or telnet to a browser if you cannot do so.
Cello Browser from Cornell LII. Available by anonymous FTP from
ftp.law.cornell.edu in the directory /pub/LII/cello.
Mosaic for Windows
From NCSA. Available by anonymous FTP from ftp.ncsa.uiuc.edu in
the directory PC/Windows/Mosaic.
WinWeb
From EINet. Available by anonymous FTP from ftp.einet.net in
the directory /einet/pc/winweb as the file winweb.zip.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but can
be evaluated free of charge for an unlimited period of time by
individuals. Netscape supports some of the official extended
HTML tags as well as its own variations. The 16-bit version
works under both OS/2 and Windows. Available by anonymous FTP
from the following sites (use the mirror closest to you; see
the URL above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Spry Mosaic
From Spry. Available by anonymous FTP from ftp.spry.com in the
directory AirMosaicDemo as the file AMOSDEMO.EXE. Spry Mosaic
is a commercial product but a demonstration version is
available and can be registered inexpensively. Works under
Windows and OS/2. Supports the mailto: URL, transparent GIFs,
ALT tags, hierarchical hotlists, etc.
Booklink
From Booklink. Available by anonymous FTP from ftp.booklink.com
in the directory lite; this is a demonstration version of the
full browser, which costs $99. Booklink can open many
simultaneous connections in different windows and display
images and pages progressively; at the time of this writing it
is the only browser to equal Netscape in this area. The "lite"
version can only open two simultaneous connections, however.
SlipKnot
SlipKnot is the only graphical WWW browser that operates
entirely without SLIP, PPP, an Ethernet connection, or special
server-side software (but consider TIA, section 4.12 for
another workaround). SlipKnot supports multiple fonts, inline
images, and review of documents you have already received while
new documents arrive, and it operates entirely through your
regular Unix shell account. SlipKnot does not require that
you install any new software on your Unix shell account.
(However, it is lacking certain important features as a result,
such as forms and validation; this will keep you from accessing
some web pages. SlipKnot does support the <ISINDEX> tag, which
many sites support as a simpler alternative to forms.) You can
obtain SlipKnot by anonymous FTP from ftp.netcom.com in the
directory pub/pbrooks/slipknot or from oak.oakland.edu in the
directory SimTel/win3/internet. For more information, see the
SlipKnot information page (URL is
http://www.interport.net/slipknot/slipknot.html ) or send a
blank email message to slipknot@micromind.com.
IBM OS/2 WebExplorer
A native IBM OS/2 web browser. WebExplorer is a multithreaded
application and replaces the usual "back" and "forward" buttons
with a visual map of your exploration of the web. IBM
WebExplorer can be acquired by anonymous FTP from
ftp01.ny.us.ibm.net in the directory pub/WebExplorer/ .
4.3.2: MSDOS BROWSERS
NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
networking on your PC. SLIP or PPP can be accomplished over phone
lines. You can do this one of two ways: using a proper SLIP account,
which requires the active cooperation of your network provider or
educational institution, or using The Internet Adapter (section 4.12),
a product which simulates SLIP through your dialup Unix shell account.
If you only have non-Unix based dialup shell access, or have no PC at
home, your best option at this time is to run Lynx on the VMS (or
Unix, or...) system you call, or telnet to a browser if you cannot do
so.
DosLynx
DosLynx is an excellent text-based browser for use on DOS
systems. You must have a level 1 packet driver, or an emulation
thereof, or you will only be able to browse local files;
essentially, if your PC has an Ethernet connection, or you have
SLIP, you should be able to use it. DosLynx can view GIF
images, but not when they are inline images (as of this
writing). See the README.HTM file at the DosLynx site for
details. You can obtain DosLynx by anonymous FTP from
ftp2.cc.ukans.edu in the directory pub/WWW/DosLynx; the URL is
ftp://ftp2.cc.ukans.edu/pub/WWW/DosLynx/.
4.3.3: MACINTOSH BROWSERS
NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
networking on your PC. SLIP or PPP can be accomplished over phone
lines. You can do this one of two ways: using a proper SLIP account,
which requires the active cooperation of your network provider or
educational institution, or using The Internet Adapter (section 4.12),
a product which simulates SLIP through your dialup Unix shell account.
If you only have non-Unix based dialup shell access, or have no PC at
home, your best option at this time is to run Lynx on the VMS (or
Unix, or...) system you call, or telnet to a browser if you cannot do
so.
Mosaic for Macintosh
From NCSA. Full featured. Available by anonymous FTP from
ftp.ncsa.uiuc.edu in the directory Mac/Mosaic.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but is
free for personal use by individuals. Version 0.9 (available to
the public as of this writing) does not support printing, but
this is promised in the forthcoming version 1.0. Contrary to
popular myth, version 1.0 will be free for personal use, just
like version 0.9. Available by anonymous FTP from the
following sites (use the mirror closest to you; see the URL
above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Samba From CERN. Basic. Available by anonymous FTP from info.cern.ch
in the directory /ftp/pub/www/bin as the file mac.
MacWeb
From EINet. Has features that Mosaic lacks; lacks some features
that Mosaic has. Available by anonymous FTP from ftp.einet.net
in the directory einet/mac/macweb.
4.3.4: AMIGA BROWSERS
AMosaic
Browser for AmigaOS, based on NCSA's Mosaic. Supports older
Amigas as well as the newer machines in the latest versions;
available for anonymous ftp from max.physics.sunysb.edu in the
directory /pub/amosaic, or from aminet sites in
/pub/aminet/comm/net. see the site for details. See the URL
http://insti.physics.sunysb.edu/AMosaic/home.html .
Emacs-W3
The Emacs-W3 browser works under Gnu Emacs on the Amiga (see
section 4.3.7).
4.3.5: NEXTSTEP BROWSERS
Note: NeXTStep systems can also run X-based browsers using one of the
widely used X server products for the NeXT. The browsers listed here,
by contrast, are native NeXTStep applications.
SpiderWoman
A brand-new (as of 12/94), multithreaded, graphical browser for
NeXTStep. Available by anonymous FTP from sente.epfl.ch in the
directory pub/software.
OmniWeb
A World Wide Web browser for NeXTStep. The URL for more
information is http://www.omnigroup.com/; you can ftp the
package from ftp.omnigroup.com in the /pub/software/ directory.
WorldWideWeb, CERN's NeXT Browser-Editor
A browser/editor for NeXTStep. Currently out of date; editor
not operational. Allows wysiwyg hypertext editing. Requires
NeXTStep 3.0. Available for anonymous FTP from info.cern.ch in
the directory /pub/www/src.
4.3.6: X/DECWINDOWS (GRAPHICAL UNIX, VMS) BROWSERS
NCSA Mosaic for X
Unix browser using X11/Motif. The original multimedia browser.
Full http 1.0 support including PUT-method forms, image maps,
etc. Recent beta versions have limited support for tables.
Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
directory Mosaic.
NCSA Mosaic for VMS
Browser using X11/DecWindows/Motif. For the VMS operating
system. Full http 1.0 support including PUT-method forms, image
maps, etc. Probably the best browser available for VMS.
Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
directory Mosaic.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but is
free for personal use by individuals. Version 0.9 (available to
the public as of this writing) does not support printing, but
this is promised in the forthcoming version 1.0. Contrary to
popular myth, version 1.0 will be free for personal use, just
like version 0.9. Available by anonymous FTP from the
following sites (use the mirror closest to you; see the URL
above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Quadralay GWHIS Viewer (Commercial Mosaic)
Quadralay offers a commercial-grade (not free!) version of
Mosaic for Unix systems, with Windows and Macintosh versions
expected in the future. (URL is:
http://www.quadralay.com/products/products.html#gwhis )
tkWWW Browser/Editor for X11
Unix Browser/Editor for X11. (Beta test version.) Available for
anonymous ftp from harbor.ecn.purdue.edu in the directory
tkwww[extension] (followed by an extension possibly dependent
on the current version). Please ftp to the site and look for
the latest version (or use the link above). Supports WSYIWYG
HTML editing.
MidasWWW Browser
A Unix/X browser from Tony Johnson. (Beta, works well.)
Viola for X (Beta)
Viola has two versions for Unix/X: one using Motif, one using
Xlib (no Motif). Handles HTML Level 3 forms and tables. Has
extensions for multiple columning, collapsible/expandable list,
client-side document include. Available by anonymous FTP from
ora.com in /pub/www/viola. More information available at the
URL http://xcf.berkeley.edu/ht/projects/viola/README.
Chimera
Unix/X Browser using Athena (doesn't require Motif). Supports
forms, inline images, etc.; closest to Mosaic in feel of the
non-Motif X11 browsers. Available for anonymous FTP from
ftp.cs.unlv.edu in the directory /pub/chimera.
Emacs w3 mode
The Emacs w3 mode supports multiple fonts, color, inline
images, movies, and the whole nine yards when run under a
graphical version of emacs; see section 4.3.7.
Arena Arena's primary purpose is to be a testbed for HTML Level 3
documents. As a result, Arena supports many of the new and
interesting features of HTML Level 3. As of this writing it is
still in prerelease and expectations should be set accordingly!
Available by anonymous FTP from ftp.w3.org in the directory
pub/www/arena/ .
4.3.7: Text-mode Unix and VMS browsers
These are text-based browsers for Unix (and in some cases also VMS)
systems. In many cases your system administrator will have already
installed one or more of these packages; check before compiling your
own copy.
Line Mode Browser
This program gives W3 readership to anyone with a dumb
terminal. A general purpose information retrieval tool.
Available by anonymous ftp from info.cern.ch in the directory
/pub/www/src.
The "Lynx" full screen browser
This is a hypertext browser for vt100s using full screen, arrow
keys, highlighting, etc. Available by anonymous FTP from
ftp2.cc.ukans.edu.
Tom Fine's perlWWW
A tty-based browser written in perl. Available by anonymous FTP
from archive.cis.ohio-state.edu in the directory pub/w3browser
as the file w3browser-0.1.shar.
For VMS
Dudu Rashty's full screen client based on VMS's SMG screen
management routines. Available by anonymous FTP from
vms.huji.ac.il in the directory www/www_client.
Emacs w3-mode
A WWW browser for emacs. Runs under Xwindows, NeXTstep, VMS,
OS/2, Windows NT, Windows 3.1, AmigaDOS, or just about any Unix
system. Also has fonts, color, inline images, and mouse support
if using Lemacs, Epoch, or Emacs 19. Also works in local mode
under DOS and on the Macintosh. Available by anonymous ftp from
ftp.cs.indiana.edu in the directory pub/elisp/w3.
4.3.8: VM/CMS BROWSERS
Albert
A WWW browser for the VM/CMS operating system. Available by
anonymous FTP from gopher.ufl.edu in the directory pub/vm/www/.
4.3.9: BATCH-MODE "BROWSERS"
Batch mode browser
A batch-mode "browser", url_get, which is available through the
URL http://www.utexas.edu/~zippy/url_get.html . It can be
retrieved via anonymous FTP to ftp.cc.utexas.edu, as the file
/pub/zippy/url_get.tar.Z. This package is intended for use in
cron jobs and other settings in which fetching a page in a
command-line fashion is useful.
4.4: How can I access the web through a firewall?
A "proxy server" is a specialized HTTP server which (typically) runs
on a firewall machine, providing access to the outside world for
people inside the firewall. The CERN httpd can be configured to run as
a proxy. Furthermore, it is able to perform caching of documents,
resulting in faster response times.
If you cannot arrange to run a proxy server (definitely the
recommended approach), read on:
For information on using NCSA Mosaic from behind a firewall, please
read the following. In general, browsers can be made useful behind
firewalls through the use of a package called "SOCKS"; the source must
be modified slightly and rebuilt to accommodate this. Whenever
possible, work with your network administrators to solve the
problem, not against them.
An excerpt from the NCSA Mosaic FAQ:
NCSA Mosaic requires a direct internet connection to work, but some
folks have put together a package that works behind firewalls. This is
completely unsupported by NCSA, but here is the latest announcement:
November 15, 1993: C&C Software Technology Center (CSTC) of NEC
Systems Lab has made available a version of SOCKS, a package for
running Internet clients from behind firewalls without breaching
security requirements, that includes a suitably modified version of
Mosaic for X 2.0. Beware: such a version is not supported by NCSA;
we can't help with questions or problems arising from the
modifications made by others. But, we encourage you to check it
out if it's interesting to you. Questions and problem notifications
can be sent to Ying-Da Lee (ylee@syl.dl.nec.com).
4.5: What is on the web?
Currently accessible through the web:
* anything served through gopher
* anything served through WAIS
* anything on an FTP site
* anything on Usenet
* anything accessible through telnet
* anything in hytelnet
* anything in hyper-g
* anything in techinfo
* anything in texinfo
* anything in the form of man pages
* sundry hypertext documents
4.5.1: HOW DO I FIND OUT WHAT'S NEW ON THE WEB?
comp.infosystems.www.announce
The newsgroup comp.infosystems.www.announce carries
announcements of new resources on the World Wide Web. Since
newsgroups are distributed, it can be accessed reliably even
when the net is very busy.
What's New With NCSA Mosaic
The unofficial newspaper of the World Wide Web is What's New
With NCSA Mosaic (URL is
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html )
, which carries announcements of new servers on the web and
also of new web-related tools. This should be in your hot list
if you're not using Mosaic (which can access it directly
through the help menu).
comp.internet.net-happinings
You can also check out the newsgroup
comp.internet.net-happenings, which carries WWW announcements
and many other Internet-related announcements.
4.5.2: WHERE IS THE SUBJECT CATALOG OF THE WEB?
There are several. There is no mechanism inherent in the web which
forces the creation of a single catalog (although there is work
underway on automatic mechanisms to catalog web sites). The best-known
catalog, and the first, is The WWW Virtual Library (URL is
http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html ),
maintained by CERN. The Virtual Library is a good place to find
resources on a particular subject, and has separate maintainers for
many subject areas.
There is also a newer cataloging system called ALIWEB that requires
very little effort to maintain and is growing rapidly (URL is
http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
4.5.3: HOW CAN I SEARCH THROUGH ALL WEB SITES?
Several people have written robots which create indexes of web sites
-- including sites which have not arranged to be mentioned in the
newspapers and catalogs above. (Before writing your own robot, please
read the section on robots.)
Here are a few such automatic indexes you can search:
* WebCrawler (URL is
http://webcrawler.cs.washington.edu/WebCrawler/WebQuery.html )
builds an impressively complete index; on the other hand, since it
indexes the content of documents, it may find many links that
aren't exactly what you had in mind. However, it does a good job
of sorting the documents it finds according to how closely they
match your search.
* World Wide Web Worm (URL is
http://www.cs.colorado.edu/home/mcbryan/WWWW.html ) builds its
index based on page titles and URL contents only. This is somewhat
less inclusive, but pages it finds are more likely to be an exact
match with your needs.
* Lycos (URL is http://fuzine.mt.cs.cmu.edu/mlm/lycos-home.html ) is
another web-indexing robot, which includes the ability to submit
the URLs of your own documents by hand, ensuring that they are
available for searching.
You can read about other robots in the robots section.
4.6: How can I save an inline image to disk?
Here are two ways:
1. Turn on "load to local disk" in your browser, if it has such an
option; then reload images. You'll be prompted for filenames instead
of seeing them on the screen. Be sure to shut it off when you're done
with it.
2. Choose "view source" and browse through the HTML source; find the
URL for the inline image of interest to you; copy and paste it into
the "Open URL" window. This should load it into your image viewer
instead, where you can save it and otherwise muck about with it.
4.7: How can I get sound from the PC speaker with WinMosaic?
This piece of wisdom donated by Hunter Monroe:
This section explains how to install sound on a PC which already has a
working version of Mosaic for Microsoft Windows. Be warned in advance
that the results may be poor.
To get Mosaic to produce sound out of the PC speaker, first, you need
a driver for the speaker. You can get the Microsoft speaker driver
from the URL ftp://ftp.microsoft.com/Softlib/MSLFILES/SPEAK.EXE or by
doing an Archie search to find it somewhere else. SPEAK.EXE is a
self-extracting file. Copy the speak.exe file to a new directory, and
then type "SPEAK" at the DOS prompt. Do not put the file SPEAKER.DRV
in a separate directory from OEMSETUP.INF.
Now, you need to install the driver. In Windows, from the Program
Manager choose successively Main/Control Panel/Drivers/Add/Unlisted or
updated drivers/(enter path of SPEAK.EXE)/PC Speaker. At this point
some strange sounds come out as the driver is initialized. Change the
settings to improve the sound quality on the various sounds: tada,
chimes, etc. Click OK when you are finished and choose the Restart
windows option.
Having installed the speaker driver, you will now get sounds whenever
you start Windows, make a mistake, or exit Windows. If you do not want
this, from the Main/Control Panel/Sounds menu, make sure there is no X
next to "Enable System Sounds."
Now, you need a sound viewer program that Mosaic can call to display
sounds. NCSA unfortunately recommend WHAM, which does not work well
with a PC speaker. Get the program WPLANY instead. You can find a copy
nearby with an Archie search on the string "wplny"; the current
version is WPLNY09B.ZIP. For details on archie and other basic issues
related to FTP, please read the Usenet newsgroup
news.announce.newusers.
Move the zip file to a new directory, and use an unzip program like
pkunzip to unzip it, producing the files WPLANY.EXE and WPLANY.DOC.
Then edit the MOSAIC.INI file to remove the "REM" before the line
"TYPE9=audio/basic". Then, you need lines in the section below that
read something like: audio/basic="c:\wplany\wplany.exe %ls"
audio/wav="c:\wplany\wplany.exe %ls" where you have filled in the
correct path for wplany.exe. The MOSAIC.INI file delivered with Mosaic
may have NOTEPAD.EXE on the audio/basic line, but this will not work.
Now, restart Mosaic, and you should now be able to produce sounds. To
check this, with Mosaic choose File/Local File/\WINDOWS\*.WAV and then
try to play TADA.WAV. Then, you might try the Mosaic Demo document for
some .AU sounds, but you are lucky if your speaker produces something
you can understand.
4.8: I have a Windows PC or Macintosh. Why can't I access WAIS URLs?
This answer provided by Michael Grady (m-grady@uiuc.edu):
The version of Mosaic for X has "wais client" code built-in to it.
This was relatively easy for the developers to do, because there was
already a set of library routines for talking to WAIS available for
Unix as "public domain" (freeWAIS). I don't think there is such a
library of routines for PC/Windows or Mac, which would make it much
more difficult for the Mosaic versions for Windows and the Mac to add
"wais client" capability. Therefore, at least for now, neither the
Windows or Mac versions of Mosaic support direct query of a WAIS
server (i.e. can act as wais clients themselves).
4.9: I'm running XMosaic. Why can't I get external viewers working...
... No matter what no matter what I do to my .mailcap and .mime.types
files?
Answer provided by Ronald E. Daniel (rdaniel@acl.lanl.gov):
Mosaic only looks at the .mime.types file if it has no idea what the
document's type is. This is actually a very rare situation.
Essentially all servers now use the HTTP/1.0 protocol, which means
that they tell Mosaic (or other browsers) what the document's MIME
Content-type is. The servers use a file very much like Mosaic's
.mime.types file to infer the Content-type from the filename's
extension.
It is pretty simple to find out if this really is the problem. Use
telnet to talk to the server and find out if it is assigning a MIME
type to the document in question. Here's an example, looking at the
home page for my server. (idaknow: is my shell prompt)
idaknow: telnet www.acl.lanl.gov 80 // Connect to the httpd server
Trying 128.165.148.3 ...
Connected to www.acl.lanl.gov.
Escape character is '^]'.
HEAD /Home.html HTTP/1.0 // replace Home.html with your
documen
t
// you supply the blank line
HTTP/1.0 200 OK // the rest of this comes from the
serve
r Date: Wednesday, 25-May-94 19:18:11 GMT
Server: NCSA/1.1
MIME-version: 1.0
Content-type: text/html // Here's the MIME Content-type
Last-modified: Monday, 16-May-94 16:21:58 GMT
Content-length: 1727
Connection closed by foreign host.
idaknow:
In the example above, /Home.html will get
http://www.acl.lanl.gov/Home.html .
Normally servers will be configured to supply a Content-type of
text/plain if they don't know what else to do. If this is the
problem you are having, take a look at the TypesConfig documentation
for NCSA's httpd. You can have the server look at the filename
extension, supply the correct Content-type, then use your local
.mailcap file to tell Mosaic what viewer to use to look at the
document.
Russ Segal adds:
The answer from Ronald Daniel is essentially correct, but it needs a
small addendum.
When starting Moasic, you can specify a "fileProxy" which will fetch
files for you:
"*fileProxy: http://socks/"
If you do this, file: URLs are no longer strictly local accesses. So
even if the URL is not fttp:, the proxy server must be upgraded as
Mr. Daniel suggests.
4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?
Programs that automatically traverse the web can be quite useful, but
have the potential to make a serious mess of things. Robots have been
written which do a "breadth-first" search of the web, exploring many
sites in a gradual fashion instead of aggressively "rooting out" the
pages of one site at a time. Some of these robots now produce
excellent indexes of information available on the web.
But others have written simple depth-first searches which, at the
worst, can bring servers to their knees in minutes by recursively
downloading information from CGI script-based pages that contain an
infinite number of possible links. (Often robots can't realize this!)
Imagine what happens when a robot decides to "index" the CONTENTS of
several hundred mpeg movies. Shudder.
The moral: a robot that does what you want may already exist; if it
doesn't, please study the document World Wide Web Robots, Wanderers
and Spiders (URL is: http://web.nexor.co.uk/mak/doc/robots/robots.html
) and learn about the emerging standards for exclusion of robots from
areas in which they are not wanted. You can also read about existing
robots there.
4.11: How do I send newsgroup posts in HTML to my web client?
How to do this depends greatly on your system; if you have a Mac or
Windows system, the answer is completely different. But, as food for
thought, here is a simple shell script I use on my Unix account to
send posts from rn and related newsreaders to Lynx. Put this text in
the file "readwebpost" and use the "chmod" command to make it
executable, then put it somewhere in your path (such as your personal
bin directory):
#!/bin/sh
echo \<PRE\> > .article.html
cat >> .article.html
echo \</PRE\> >> .article.html
lynx .article.html < /dev/tty
rm .article.html
Then add the following line to your .rnmac file (create it if you
don't already have one):
W |readwebpost %C
Now, when you press "W" while reading a post in rn, a message will be
sent to Lynx, and the links enclosed in it will be live.
Larry W. Virden provides the following version which invokes Mosaic
instead, and is also capable of communicating with an already-running
copy of Mosaic instead of launching another. (You can use the same rn
macro as above, invoking "goto-xm" instead of "readwebpost".) Read the
comments for details on the assumptions made by the script.
#! /bin/sh
# goto-xm, by Joseph T. Buck <jbuck@eecs.berkeley.edu>
# Modified heavily by Larry W. Virden <lvirden@cas.org>
# Script for use with newsreaders such as trn. Piping the article
# through this command causes xmosaic to pop up, pointing to the
# article. If an existing xmosaic (version 1.1 or later) exists,
# the USR1 method will be used to cause it to point to the correct
# article, otherwise a new one will be started.
# assumptions: ps command works as is on SunOS 4.1.x, may need changes
# on other platforms.
URL=`/bin/grep '^Message-ID:' | /bin/sed -e 's/.*</news:/' -e 's/>.*//'`
if [ "X$URL" = "X" ]; then
echo "USAGE: $0 [goto] [once] < USENET_msg" >&2
exit 1
fi
pid=`ps -xc | egrep '[Mm]osaic' | awk 'NR == 1 {print $1}'`
p=`which Mosaic`
gfile=/tmp/Mosaic.$pid
$p "$URL" &
if [ "$#" -gt 0 ] ; then
if [ "$1" = "goto" -o "$1" = "same" ] ; then
shift
echo "goto" > $gfile
else
echo "newwin" > $gfile
fi
else
echo "newwin" > $gfile
fi
/bin/awk 'END { printf "'"$URL"'" }' </dev/null >> $gfile
trap "echo signal encountered" 30
kill -USR1 $pid
exit 0
See also MosaicMail (URL is
http://www.oac.uci.edu/indiv/ehood/mhonarc.doc.html ), a Perl script
which pipes email and/or news to your current Mosaic session.
4.12: I can't get SLIP. I want Mosaic. Is there a way?
YES! If you have a plain old Unix shell account on a Unix system, such
as a SunOS or Ultrix system, you can do one of two things: you can run
SlipKnot, a special browser which operates using programs that may
already be installed on your shell account (see section 4.3.1), or you
can run The Internet Adapter (TIA), a program which provides a
pseudo-SLIP connection. The remainder of this section focuses on TIA.
TIA is not free software, but there is a free two-week trial period
and it is very cheap to register.
"So what do I run on my machine at home?"
Exactly the same software you would use for real SLIP; as far as your
PC is concerned, it is a SLIP connection. If you're unfamiliar with
SLIP please check out a newsgroup relevant to your particular type of
PC (Windows, Mac, etc). (This isn't restricted to common systems;
because all the emulation happens on your Unix shell account, your
client machine can run anything that supports SLIP.)
"Details, please! I'm confused."
Check out the TIA home page (URL is
http://marketplace.com/tia/tiahome.html ), or send email to
info@marketplace.com and request details about TIA.
If you have a Macintosh, check out the Macintosh TIA Users' FAQ (URL
is: ftp://ftp.netcom.com/pub/bi/billa/tia/faq.html ) for additional
help.
Archive-name: www/faq/part2
Last-modified: 1995/26/1
5.1: HOW CAN I PROVIDE INFORMATION TO THE WEB?
Information providers run programs that the browsers can obtain
hypertext from. These programs can either be WWW servers that
understand the HyperText Transfer Protocol HTTP (best if you are
creating your information database from scratch), "gateway" programs
that convert an existing information format to hypertext, or a
non-HTTP server that WWW browsers can access -- anonymous FTP or
gopher, for example.
To learn more about World Wide Web servers, you can consult a www
server primer by Nathan Torkington, available at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-servers.html .
If you only want to provide information to local users, placing your
information in local files is also an option. This means, however,
that there can be no off-machine access.
5.2: Obtaining Servers
Servers are available for Unix, Macintosh, MS Windows, Windows NT,
OS/2, and VMS systems. If you know of a server for another operating
system, please contact me.
See http://info.cern.ch/hypertext/WWW/Daemon/Overview.html for more
information on writing servers and gateways in general.
5.2.1: UNIX SERVERS
NCSA httpd
NCSA has released a server, known as the NCSA httpd; it is
available at the URL ftp://ftp.ncsa.uiuc.edu/Web/ncsa_httpd .
EIT httpd
EIT has created the Webmaster's Starter Kit, which installs
their WWW server on your system via the web through a painless
forms interface. Recommended for those unfamiliar with server
installation. You can learn more about the starter kit and the
EIT httpd at the starter kit site (URL is
http://wsk.eit.com/wsk/doc/ ).
CERN httpd
CERN's server is available for anonymous FTP from info.cern.ch
(URL is http://info.cern.ch/hypertext/WWW/Daemon/Status.html )
and many other places. Use your local copy of archie to search
for "www" in order to find a nearby site.
GN Gopher/HTTP server
The GN server is unique in that it can serve both WWW and
Gopher clients (in their native modes). This is a good server
for those migrating from Gopher to WWW, although it does not
have the server-side-script capabilities of the NCSA and CERN
servers. See the URL http://hopf.math.nwu.edu/ .
Perl server
There is also a server written in the Perl scripting language,
called Plexus, for which documentation is available at the URL
http://bsdi.com/server/doc/plexus.html .
WN Server
The WN Server, available at the URL
http://hopf.math.nwu.edu/docs/manual.html , is designed with an
emphasis on security and flexibility, and takes a different
approach from the NCSA and CERN servers. It provides text
searching facilities as a standard feature.
5.2.2: MACINTOSH SERVERS
There is a server for the Macintosh, MacHTTP, available at the URL
http://www.uth.tmc.edu/mac_info/machttp_info.html .
5.2.3: MS WINDOWS, IBM OS/2 AND MS WINDOWS NT SERVERS
HTTPS (Windows NT)
HTTPS is a server for Windows NT systems, both Intel and Alpha
-- based. It is available via anonymous FTP from emwac.ed.ac.uk
in the directory pub/https (URL is
ftp://emwac.ed.ac.uk/pub/https). (Be sure to download the
version appropriate to your processor.) You can read a detailed
announcement at the FTP site, or by using the URL
ftp://emwac.ed.ac.uk/pub/https/https.txt.
A professional version is also available (URL is
http://emwac.ed.ac.uk/html/internet_toolchest/https/prof.htm ).
NCSA httpd for Windows
The NCSA httpd for Windows has most of the features of the Unix
version, including scripts (which generate pages on the fly
based on user input). It is available by anonymous FTP from the
ftp site ftp.alisa.com in the directory pub/win-httpd, and
documentation can be found at the URL
http://www.alisa.com/win-httpd/index.html .
SerWeb
A simple, effective server for Windows writtten by Gustavo
Estrella. Available by anonymous ftp from
winftp.cica.indiana.edu (or one of its mirror sites, such as
nic.switch.ch), as the file serweb03.zip, in the directory
/pub/pc/win3/winsock.
There is also a Windows NT version of SerWeb, available by
anonymous FTP from emwac.ed.ac.uk as /pub/serweb/serweb_i.zip.
WEB4HAM
Another Windows-based server, available by anonymous FTP from
ftp.informatik.uni-hamburg.de as /pub/net/winsock/web4ham.zip.
OS2HTTPD
An OS/2 server, written by Frankie Fan. See the home page (URL
is ftp://ftp.netcom.com/pub/kf/kfan/overview.html ) for
details, or fetch the package by anonymous FTP from
ftp.netcom.com in the directory pub/kf/kfan.
5.2.4: MSDOS AND NOVELL NETWARE SERVERS
KA9Q KA9Q NOS (nos11c.exe) is a internet server package for DOS that
includes HTTP and Gopher servers. It can be obtained via
anonymous FTP from one of the following sites:
inorganic5.chem.ufl.edu
biochemistry.cwru.edu
GLACI-HTTPD
GLACI-HTTPD is a Netware Loadable Module which allows a Novell
NetWare server to become a World Wide Web server (URL is
http://www.glaci.com/info/glaci-httpd.html ).
5.2.5: VMS SERVERS
CERN HTTP for VMS
A port of the CERN server to VMS. Available at the URL
http://delonline.cern.ch/disk$user/duns/doc/vms/distribution.html .
Region 6 Threaded HTTP Server
A native VMS server which uses DECthreads(tm). This is a
potentially major performance advantage because VMS has a high
overhead for each process, which is a problem for the
frequently-forking NCSA and CERN servers that began life under
Unix. A multithreaded server avoids this overhead. Available at
the URL http://kcgl1.eng.ohio-state.edu/www/doc/serverinfo.html .
5.2.6: AMIGA SERVERS
NCSA's Unix server has been ported to the Amiga, and is bundled with
the AMosaic browser. See the URL
http://insti.physics.sunysb.edu/AMosaic/home.html for details.
5.2.7: VM/CMS SERVERS
A VM/CMS web server is available; see the URL
http://ua1vm.ua.edu/~troth/rickvmsw/rickvmsw.html for more
information. If you don't yet have a web browser to try this URL with,
check out the VM/CMS Browsers section.
5.2.8: YEAH, BUT WHICH IS BEST?
To find out which server is best for your needs, you will want to
consult Paul Hoffman's Server Comparison Chart (URL is
http://sunsite.unc.edu/boutell/faq/chart.html ). That document is also
available by anonymous FTP from ftp.netcom.com in the directory
pub/bo/boutell/faq.
5.3: Producing HTML documents
HTML is the simple markup system used to create hypertext documents.
There are three ways to produce HTML documents: writing them yourself,
which is not a very difficult skill to acquire, using an HTML editor,
which assists in doing the above, and converting documents in other
formats to HTML. The following three sections cover these
possibilities in sequence.
5.3.1: WRITING HTML DOCUMENTS YOURSELF
You can write an HTML document with any text editor. Try the "source"
button of your browser (or "save as" HTML) to look at the HTML for a
page you find particularly interesting. The odds are that it will be a
great deal simpler than you would expect. If you're used to marking up
text in any way (even red-pencilling it), HTML should be rather
intuitive.
A beginner's guide to HTML is available at the URL
http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html . You
can also find a plain text version (at the URL
ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.txt) and a compressed
Postscript version (at the URL
ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.ps.Z). (Since the
latter two are FTP URLs, you can fetch them by hand using FTP if you
do not yet have a web browser.)
There is also an HTML primer by Nathan Torkington at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-html.html .
5.3.2: HTML EDITORS
Of course, most folks would still prefer to use a friendlier,
graphical editor. Some editors are WYSIWYG (What You See Is What You
Get), or close to it; others simply assist you in writing HTML by
plugging in the desired markup tags for you from a menu.
Fans of the EMACS editor can use EMACS and html-helper-mode , an EMACS
"mode" for HTML editing (URL is http://www.reed.edu/~nelson/tools/ ).
There is also another Emacs HTML mode, html-mode.el (URL is
ftp://ftp.ncsa.uiuc.edu/Web/html/elisp/html-mode.el ).
For Microsoft Windows users, there is an editor called HTML Assistant
with features to assist in the creation of HTML documents. It can be
had by anonymous FTP from ftp.cs.dal.ca in the directory /htmlasst/.
Read the README.1ST file in this directory for information on which
files to download.
ANT_HTML.DOT is a Word for Windows 6.0 template designed to convert
Word documents into HTML documents in a WYSIWYG environment. It
includes a demo version of the ANT_PLUS utility, which converts HTML
files to WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or
any other format possible in Word 6.0. Contact jswift@freenet.fsu.edu
if you need more information.
A WYSIWYG editor for the Web, SoftQuad HoTMetaL, is available for
downloading at NCSA and numerous other sites. Many mirror sites exist;
if you can't get through to one, try another, don't give up! That's
what mirror sites are for. (Also be sure to use the copy closest to
you geographically if possible.) Hotmetal is available for both Sun
Sparc systems and Windows systems; note that Windows users need at
least 6 megabytes of free memory. (A 2-megabyte swap file should just
barely do the trick on a 4MB machine.)
Known mirrors:
* ftp://ftp.ncsa.uiuc.edu/Web/html/hotmetal/
* ftp://ftp.ifi.uio.no/pub/SGML/HoTMetaL
* ftp://sgml1.ex.ac.uk/SoftQuad
* ftp://src.doc.ic.ac.uk/packages/WWW/ncsa/html/hotmetal/
*
ftp://askhp.ask.uni-karlsruhe.de/pub/infosystems/mosaic/contrib/Sof
tQuad
* ftp://ftp.cs.concordia.ca/pub/www
*
You need a Sun SPARC or Microsoft Windows system and 6MB of disk (6MB
of RAM minimum for MS Windows; swap files count). Other Unix systems
may be supported by the time you read this; have a look on one of the
sites above.
Because it is context-sensitive, HoTMetaL guides users in creating new
HTML documents and in cleaning up old ones. A Publish command changes
appropriate SRC and HREF attributes from local paths to http
locations. For more information, FTP the README file from the same
directory, or send email to hotmetal@sq.com. A HoTMetaL Pro
commercially supported version is available for purchase from SoftQuad
and its resellers.
Also see Gabriel White's reviews of MS Windows HTML editors (URL is
http://werple.mira.net.au/%7Egabriel/web/html/editors/ ). Another
option, if you have an SGML editor, is to use it with the HTML DTD
(URL is http://info.cern.ch/hypertext/WWW/MarkUp/DTDHeading.html ).
An editor for all X users: TkWWW (listed above under X browsers)
supports WYSIWYG HTML editing; and since it's a browser, you can try
out links immediately after creating them.
Another editor for X users: Phoenix (URL is
http://www.bsd.uchicago.edu/ftp/pub/phoenix/README.html ) is a fully
WYSIWYG HTML editor which insulates the user from direct control of
the HTML tags. Available by anonymous FTP from www.bsd.uchicago.edu in
the pub/phoenix subdirectory.
Also for X users, there is a package called htmltext which supports
WYSIWYG HTML editing. More information is available at the URL
http://web.cs.city.ac.uk/homes/njw/htmltext/htmltext.html .
For Macintosh users, there is a near-WYSIWYG package called HTML
Editor (URL is http://dragon.acadiau.ca:1667/~giles/HTML_Editor).
ANT_HTML is a Word for the Macintosh template designed to convert Word
documents into HTML documents in a WYSIWYG environment. It includes a
demo version of the ANT_PLUS utility, which converts HTML files to
WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or any other
format possible in Word. At the time of this writing it was scheduled
to have been released on the Macintosh (it has long been available for
Windows). Contact jswift@freenet.fsu.edu for more information. Also
for Macintosh users, the BBEdit HTML extensions allow the BBEdit and
BBEdit Lite text editors for the Macintosh to conveniently edit HTML
documents. (URL is http://www.uji.es/bbedit-html-extensions.html .)
You can also obtain the extensions package by anonymous ftp from
sumex-aim.stanford.edu as info-mac/bbedit-html-ext-b3.hqx.
There is an alternative BBEdit extension package available as well
(URL is http://www.york.ac.uk/~ld11/BBEditTools.html ). it is
available by FTP from ftp.york.ac.uk in the directory
/pub/users/ld11/BBEdit_HTML_Tools.sea.hqx.
NCSA's List of Filters and Editors, for which the URL is
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/faq-software.html#ed
itors, mentions several editors, including two for MS Windows. In some
cases, the "editor" amounts to a set of macros for an existing word
processor, which can provide a near-WYSIWYG environment.
Note that this URL contains uppercase and lowercase letters; certain
operating systems won't allow mixed case on the command line, or will
only allow it if it is quoted (VMS), so if you are launching Lynx or
another client and specifying a URL at the command line, try quoting
the URL in double-quotes ("URL").
5.3.3: CONVERTING OTHER FORMATS TO HTML
There is a collection of filters for converting your existing
documents (in TeX and other non-HTML formats) into HTML automatically,
including filters that can allow more or less WYSIWYG editing using
various word processors:
Rich Brandwein and Mike Sendall's List at CERN (URL is
http://info.cern.ch/hypertext/WWW/Tools/Filters.html ).
(Note that this URL contains uppercase and lowercase letters; certain
operating systems such as VMS require you to quote mixed-case URLs
when launching a borwser from the command line. This is NOT a bug in
the browser.)
There is also a Word for Windows template for writing HTML documents,
available at the URL http://www.gatech.edu/word_html/release.htm .
5.3.4: CHECKING YOUR HTML FOR ERRORS
Tools to validate your HTML documents (check them for errors) are
available. There is a form at the URL
http://www.hal.com/%7Econnolly/html-test/service/validation-form.html
which will check HTML documents for errors according to the latest
specification; note that you are encouraged to set up the program on
your own system if you make heavy use of the form. There is also a
tool which will check the links in your documents for links to
nonexistent resources, such as pages that have moved (URL is
http://wsk.eit.com/wsk/dist/doc/admin/webtest/verify_links.html ).
Also try weblint (URL is
http://www.khoros.unm.edu/staff/neilb/weblint.html ), a Perl script
that checks your HTML for errors; you can even try it out over the web
through an HTML form. The script is available by anonymous FTP from
ftp.khoros.unm.edu in the directory pub/perl/www.
Another such tool is htmlchek (URL is:
http://uts.cc.utexas.edu/~churchh/htmlchek.html ), which checks HTML
documents for errors, creates a cross-reference, automatically expands
entities (such as European characters) to their proper HTML form, and
performs other useful services. htmlchek is available by anonymous FTP
from ftp.cs.buffalo.edu in the directory pub/htmlchek.
5.4: How do I publicize my work?
There are several things you can do to publicize your new HTML server
or other offering:
* Post to comp.infosystems.www.announce. PLEASE READ THE CHARTER
POSTING FIRST. In general, always read a newsgroup first to
familiarize yourself before posting to it.
* Submit it to the NCSA What's New Page at the URL
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html
(see the page for details on how to submit your listing!).
* Post it to the newsgroup comp.infosystems.announce. Please read
the group first to get a feel for the contents. You should not
post to comp.infosystems.www.users,.misc,.providers, etc., but if
you feel compelled to do so, please choose .misc as announcements
are of interest to both providers and users (and those who wear
both hats).
* Submit it to the maintainers of various catalogs, such as the WWW
Virtual Library (at the URL
http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html
) and the ALIWEB index (at the URL
http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
* Read Gareth Rees' guide to publishing on the World Wide Web. (URL
is http://www.cl.cam.ac.uk/users/gdr11/publish.html ).
5.5: Can I buy space on an existing server?
Yes, you can. A list of sites offering WWW space for lease is
available (at the URL http://union.ncsa.uiuc.edu/www/leasing.shtml ).
5.6: How fast does my net connection need to be?
The following response to this very-frequently-asked-question was
provided by Mike Meyer (mwm@contessa.phone.net).
The answer is "It depends." What it depends on is what kind of
things you want to provide on your server. Here are some rules of
thumb to use when deciding what kind of connection you need for your
server.
The first rule of thumb is:
Don't worry about simultaneous access.
Unless you have a very large site, simultaneous access is not a
problem. If you have a very large site, you need as much bandwidth
as you can afford. There is a bit more about this below.
The second rule of thumb is:
It should take at most 5 seconds to send a page.
The five second rule dates from command line days, when that was
about how long people would wait before getting impatient with the
system. It seems like a reasonable number to use now.
Since external images/audio/etc. are somewhat exceptional, allow
more time for them. If you think they should have the same
restrictions as above, buy the bandwidth your site will need to do
so. However, the rule of thumb for external images/audio/etc is:
It should take at most 30 seconds to send an external file.
Given these rules, it's pretty straightforward to work out how large
an HTML page and external files can be. At least, it's easy after
you simplify things by ignoring IP overhead on the line, compression
on modem lines, and anything that's less than 10% of the total (or
even a little bit more than 10%).
The one simplification not to ignore is the multiple packet
round-trips it takes to get data flowing through an HTTP channel.
For modem lines, this is nearly a second for each HTTP connection,
which is significant. For leased lines, it's more like .1 or .2
seconds, which is not significant.
On a 14.4 line assumed to be sending 1.4K bytes of data/second, with
a 1 second startup, you get 4 * 1.4 or 5.6K of HTML. If you want to
include a single inline image, that's 2 seconds of startup, so
you're down to 3 * 1.4 or 4.2K of HTML + image. This means smallish
HTML pages, and simple inline images. For external files, you get 29
* 1.4 or 40K, which is still a small image. If you have a 28.8 line,
you get to double those figures; for a 9600 line, figure 2/3rds of
that size.
On a 56K leased line assumed to be sending 5K/second, you get 25K of
HTML, or mixed HTML/data. For external images, it's 150K. That
should cover any reasonable HTML document, and small to medium
external files. An MPEG movie might be a bit much.
With a T1 line assumed to be sending 150K/second, you get 750K of
HTML, or 4.5 megabytes in an external file. Barring very large
animations, this should be sufficient for anything you want to
serve. More would be faster, but it also gets drastically more
expensive.
Given the above guidelines, let's look at simultaneous access again.
Under the worst case conditions, you're using all of your line for
HTML pages, each of which takes 5 seconds to send, so your server is
sending 12 pages a minute, or 720 pages an hour, or 17,000 pages a
day (pages, not accesses; each inline image in a page generates an
access, unless the client cached it). This makes you one of the
busier sites on the web. While you'll have contention problems
before you get to this point, anything but a modem connection will
be sending most pages in a small fraction of five seconds, which
should leave plenty of bandwidth with no contention. If you have
this kind of access rates on a modem line, you should seriously
consider upgrading your connection.
The bottom line on simultaneous access is that the WWW server is
more likely to have contention with other uses of the line than with
itself. Since I don't know what else you use your line for, I can't
factor it in. You'll have to consider that issue yourself.
5.7.1: HOW DO I SET UP A CLICKABLE IMAGE MAP?
There are really two issues here: how to indicate in HTML that you
want an image to be clickable, and how to configure your server to do
something with the clicks returned by Mosaic, Chimera, and other
clients capable of delivering them.
You can read about image maps and the NCSA server at the URL
http://hoohoo.ncsa.uiuc.edu/docs/setup/admin/Imagemap.html .
Using imagemaps requires that you create a map file; you can do this
by hand or with a WYSIWYG tool.
VERY IMPORTANT: Creating imagemaps requires a real web server (not
an FTP server) and a cooperative web server administrator. It is not
usually as simple as wrapping a link around an IMG SRC tag and adding
the ISMAP directive; the server must also be told about the map file,
and the way to accomplish this varies from server to server. So read
your server documentation, and don't waste time making maps before
making sure you have the necessary tools to deliver them.
Mapedit
Mapedit (URL is:
http://sunsite.unc.edu/boutell/mapedit/mapedit.html ) is a
WYSIWYG imagemap editing tool for Microsoft Windows and the X
Window System.
MapMaker
For users of John Bradley's xv image display software for the
X Window System, Mapmaker can turn the miniature images created
by xv's Visual Schnauzer into an imagemap. This is useful if
you would like to make an entire directory of images available
(but note that you should also make textual links to allow
those with text- based browsers to download the images for
external viewing). (URL is:
http://icg.stwing.upenn.edu:80/~mengwong/mapmaker.html )
WebMap
On the Macintosh, you may want to use WebMap (URL is
ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW ). . It
produces both NCSA and CERN-compatible maps, which can also be
used with MacImagemap and a Macintosh-based server (MacImagemap
is found in the same directory). Alternatively, you may want to
use MacMapMaker, also available from
ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW (the same
directory).
Tkmapedit
For Unix systems and other systems on which the Tk/Tcl language
toolkit has been installed, Tkmapedit provides a WYSIWYG
imagemap editor which is capable of directly testing links if
the tkWWW web browser is available. Available by anonymous FTP
from the TCL archive on ftp.aud.alcatel.com.
5.7.2: HOW DO I MAKE A "LINK" THAT DOESN'T LOAD A NEW PAGE?
Such links are useful when a form is intended to perform some action
on the server machine without sending new information to the client,
or when a user has clicked in an undefined area in an image map; these
are just two possibilities.
Rob McCool of NCSA provided the following wisdom on the subject:
Yechezkal-Shimon Gutfreund (sg04@gte.com) wrote:
: Ok, here is another bizzare request from me:
: I am currently running scripts which I "DO NOT" want to return
: any visible result. That is, not text/plain, not text/HTML, not
: image/gif. The entire results are the side effects of the
: script and nothing should be returned to the viewer.
: It would be nice to have an internally supported null viewer
: so that I could do this, more "cleanly" (ok, ok, I hear your groans).
HTTP now supports a response code of 204, which is no operation. Some
browsers such as Mosaic/X 2.* support it. To use it, make your script
a nph script and output an HTTP/1.0 204 header. Something like:
HTTP/1.0 204 No response Server: Myscript/NCSA httpd 1.1
(You can learn more about nph scripts from the NCSA server
documentation at the URL http://hoohoo.ncsa.uiuc.edu/docs .)
Essentially they are scripts that handle their own HTTP response
codes.
5.7.3: WHERE CAN I LEARN HOW TO CREATE FILL-OUT FORMS?
Writing an HTML form is easy, but the form doesn't accomplish anything
until you write a CGI program to interpret the results on the server
side! For more information, see section 5.7.14.
See the section on email forms for a simple solution to the most
commonly desired form.
5.7.3.1: How can I create hidden fields in forms (keeping state)?
Use INPUT TYPE=hidden. An example:
<INPUT TYPE=hidden NAME=state VALUE="hidden info to be returned with form">
By now, most browsers can handle the hidden type, but understand that
some browsers will fail to hide the field (and probably confuse the
user). Note that "hidden" doesn't mean "secret"; the user can always
click on "view source".
5.7.3.2: How can users send me email through their browsers?
There are two ways:
Using a mailto: URL
You can simply create a link which looks like this:
<A HREF="mailto:me@my.address">Send Me Mail</A>
This works great for browsers that support the mailto: URL.
Perhaps 80% of web users will be able to use such a link. But
not all browsers support it.
Installing an email form
If you have access to the server's configuration files, or if
your server administrator permits users to create their own CGI
scripts, you can create a form which sends mail to you from any
browser that supports forms. I've written a simple email forms
package (URL is: http://siva.cshl.org/email/index.html ), which
does it in ANSI C. There is also a package written in Perl,
known as the WWW Mailto Gateway (URL is
http://www.mps.ohio-state.edu/mailto/mailto_info.html ).
GetComments (URL is:
http://everest.cs.ucdavis.edu/~hoagland/getcomments.html) is a
more general package, also written in Perl, which can handle
many different types of comment forms.
If you want to learn how these forms actually work, see section
5.7.14.
5.7.4: HOW DO I COMMENT AN HTML DOCUMENT?
Use the <!-- tag at the beginning of EACH line commented out; close
this for EACH line with the --> tag. Note that comments do not nest,
and the sequence "--" may not appear inside a comment except as part
of the closing --> tag. (It's officially allowed, but some browsers
won't handle it properly.)
You should not try to use this to "comment out" HTML that would
otherwise be shown to the user, since some browsers (notably Mosaic)
will still pay attention to tags inside the comment and close it
prematurely.
Thanks to Joe English for clearing up this issue.
5.7.5: HOW CAN I CREATE DECENT-LOOKING TABLES AND STOP USING <PRE>...
</PRE>?
Tables are a standard feature in HTML Level 3, a new version of HTML.
Unfortunately, they are at present implemented only by the latest NCSA
Mosaic versions and the Viola and Emacs-W3 browsers, to my knowledge.
In addition, most implementations are incomplete. In some
implementations, at the time of this writing, text in tables cannot be
selected and/or cannot be a link.
However, there is a way to use HTML Level 3 tables now and convert
them automatically to HTML, allowing you to design proper tables and
install those pages directly when table support arrives in the
majority of clients. You can do this using the html+tables package, by
Brooks Cutter (bcutter@paradyne.com), which is available for anonymous
ftp from sunsite.unc.edu in the directory
pub/packages/infosystems/WWW/tools/html+tables.shar. This package
requires the shell language Perl, which is primarily used on Unix
systems but is also available for other systems (such as MSDOS
machines). html+tables accepts HTML Level 3 and outputs html using the
<PRE>...</PRE> construct to represent tables, allowing you to write
HTML Level 3 now, knowing that it will look better when clients are
ready for it.
5.7.6: WHAT IS HTML LEVEL 3 AND WHERE CAN I LEARN MORE ABOUT IT?
HTML Level 3, also known as HTML+, is an enhanced version of HTML
designed to address some of the limitations of HTML. HTML Level 3
supports true tables, right-justified text, centered text, line breaks
that do not double space, and many other desired features.
However, most clients support only a handful of HTML Level 3 features
(such as the partial implementation of tables in Mosaic) at the time
of this writing. If you have access to a Unix system with the X Window
System installed, you can try out many features of HTML Level 3 using
the experimental Arena browser.
You can access information about new developments in HTML at the CERN
server (at the URL
http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html ).
(HTML Level 1 is the original version. HTML Level 2 is essentially the
same, but with the addition of forms.)
5.7.7: HOW CAN I MAKE TRANSPARENT AND INTERLACED GIFS? AND WHAT ARE THEY?
Transparent GIFs are useful because they appear to blend in smoothly
with the user's display, even if the user has set a background color
that differs from that the developer expected. They do this by
assigning one color to be transparent -- if the web browser supports
transparency, that color will be replaced by the browser's background
color, whatever it may be.
Interlaced GIFs appear first with poor resolution and then improve in
resolution until the entire image has arrived, as opposed to arriving
linearly from the top row to the bottom row. This is great to get a
quick idea of what the entire image will look like while waiting for
the rest. This doesn't do much for you if your web browser doesn't
support progressive display as the image is downloaded, but
non-progressive-display web browsers will still display interlaced
GIFs once they have arrived in their entirety.
To create transparent and interlaced GIFs, check out David Koblas'
giftool, a program which can manipulate those options and many more
aspects of your GIF file.
In addition, there is a document explaining transparent GIFs available
at the URL http://melmac.corp.harris.com/transparent_images.html . You
can fetch the program giftrans by anonymous ftp from
ftp.rz.uni-karlsruhe.de at the path /pub/net/www/tools/giftrans.c.
There is also a Perl Script (URL is:
http://www.omron.co.jp:80/~jfriedl/perl/ ) which makes transparent
GIFs.
There is also a utility for the Macintosh, Transparency (URL is:
http://www.med.cornell.edu/~giles/projects.html#transparency).
5.7.8: HOW COME MAILTO: URLS DON'T WORK?
The mailto: URL is a feature found in Lynx, Netscape, Spry Mosaic, the
latest NCSA Mosaics, Emacs w3 mode and many other browsers. In
general, about 80% of web browsers support mailto: at the time of this
writing. However, it is not in numerous older browsers. In the
meantime, you can set up forms which send mail to you; see Section
5.7.3.2.
5.7.9: HOW CAN I RESTRICT AND CONTROL ACCESS TO MY SERVER?
All major servers have features that allow you to limit access to
particular sites, and many clients have authentication features that
allow you to identify specific users. There is a tutorial on security
and user authentication with the NCSA server and Mosaic available,
written by Marc Andreessen (URL is
http://wintermute.ncsa.uiuc.edu:8080/auth-tutorial/tutorial.html ).
See your server documentation for further information.
5.7.10: WHICH FORMAT IS BETTER FOR WWW IMAGE PURPOSES, JPEG OR GIF?
JPEG does a better job with realistic images such as scanned
photographs. Most browsers cannot handle inline JPEGs, however, so you
must link to them as external images (using a regular <A HREF...>
instead of <IMG SRC...>).
GIF does a better job with crisp, sharp images, such as those
typically used to construct buttons, graphs and the like. All browsers
that can display graphics at all can display GIFs inline.
5.7.11: HOW CAN I MIRROR PART OF ANOTHER SERVER?
Scripts are available to do this, but at this time they are not very
friendly to the server you are attempting to mirror; their behavior
resembles that of the more poorly written WWW robots. If you are
trying to improve access times to a distant server, you will likely
find the "proxy" capabilities of CERN's WWW server to be a more
effective and general solution to your problem.
5.7.12: HOW CAN I KEEP ROBOTS OFF MY SERVER?
Programs that automatically traverse the web can be quite useful, but
have the potential to make a serious mess of things. Every so often
someone will write a "depth-first" searching robot that brings servers
to their knees. See the section on writing robots (4.10) for details.
Fortunately, most robots on the web follow a simple protocol by which
you can keep them off your server if you wish, or keep them out of
portions of your server which are robot traps (ie, they contain an
infinite number of possible links). Read the document World Wide Web
Robots, Wanderers and Spiders (URL is:
http://web.nexor.co.uk/mak/doc/robots/robots.html ) and learn about
the emerging standards for exclusion of robots from areas in which
they are not wanted. You can also read about existing robots there,
including useful cataloging robots you probably do not want to keep
off your server.
5.7.13: HOW CAN I KEEP STATISTICS ABOUT MY WEB SERVER?
There are several tools which can generate statistics about your web
server:
getstats
getstats is a versatile log analyzer, also written in C, which
provides reports for various time periods with a high degree of
flexibility. Add-on packages have been written to generate
reports in HTML and also to generate graphs. You can access the
getstats home page for more information (URL is
http://www.eit.com/software/getstats/getstats.html ), or obtain
the package by anonymous FTP from ftp.eit.com in the directory
/pub/web.software/getstats.
WebStat
WebStat is a package written in the language Python which
supplies statistics on usage by domain, country, etc., with
daily, weekly, monthly and annual reports available. You will
need Python in order to use it. See the WebStat home page (URL
is
http://www.pegasus.esprit.ec.org/people/sijben/statistics/advertisment.html
) for details, or obtain Python from ftp.cwi.nl in
the directory /pub/python and WebStat from
ftp.pegasus.esprit.ec.org in the directory /pub/misc.
Wusage
Wusage, which I wrote, is a C program which generates simple
weekly reports in HTML, with inline image graphs displaying
server growth and the distribution of accesses by continent.
You can also exclude irrelevant accesses (inline images, local
machines, etc.) from the results. Read the Wusage home page
(URL is http://siva.cshl.org/wusage.html ) for more
information, or obtain Wusage by anonymous FTP from
isis.cshl.org in the directory pub/wusage.
wwwstat
wwwstat is a full-featured log analyzer written in the language
Perl. (See the newsgroup comp.lang.perl for more information
about the language.) See the wwwstat home page (URL is
http://www.ics.uci.edu/WebSoft/wwwstat/ ) for more information,
or obtain the package by anonymous FTP from liege.ics.uci.edu
in the directory /pub/arcadia/wwwstat. See also gwstat (URL is
http://dis.cs.umass.edu/stats/gwstat.html ), a package which
produces GIF graphs from the output of wwwstat.
5.7.14: I WANT TO GENERATE WEB PAGES FROM A PROGRAM. DO I HAVE TO WRITE A
CUSTOM SERVER?
No, you will not need to write a custom server. Most web servers
support one variation or another of a standard for adding your own
programs to the web server. The standard is called CGI (Common Gateway
Interface).
Marc Hedlund has written a FAQ on CGI programming (URL is:
http://www.halcyon.com/hedlund/cgi-faq/ ) which makes a good
introduction to the subject. The standard itself can be found at NCSA
(URL is: http://hoohoo.ncsa.uiuc.edu/ ).
5.7.14.1: How can I generate GIFs on the fly from my CGI scripts?
If you want to generate GIF images on the fly as part of your
application, examine the gd library (URL is:
http://siva.cshl.org/gd/gd.html ). Hint: your HTML page and your
inline images are separate documents with separate URLs. Generate them
in response to separate requests! (Yes, there are tricks to speed this
up, but be careful not to break inline images on HTML pages you didn't
write that refer to your gd-generated image.)
It's also possible to use gnuplot and the pbmplus utilities. This is
slower, but can require less programming if gnuplot is sufficient for
your purposes. (See archie for both tools.)
6: WHERE CAN I DISCUSS THE WORLD WIDE WEB?
6.1: What newsgroups discuss the Web?
You can find discussion of World Wide Web topics in three newsgroups,
and one newsgroup which will soon be removed:
comp.infosystems.www.users
A forum for the discussion of WWW client software and its use
in contacting various Internet information sources. New user
questions, client setup questions, client bug reports,
resource-discovery questions on how to locate information on
the web that can't be found by the means detailed in the FAQ
and comparison between various client packages are among the
acceptable topics for this group. Please specify what browser
and what system type (Windows, Mac, Unix, etc.) your post is
about if you are asking questions about a specific program.
comp.infosystems.www.providers
A forum for the discussion of WWW server software and the use
of said software to present information to users. General
server design, setup questions, server bug reports, security
issues, HTML page design and other concerns of information
providers are among the likely topics for this group.
comp.infosystems.www.misc
A forum for general discussion of WWW (World Wide Web)- related
topics that are NOT covered by the other newsgroups in the
hierarchy. This will likely include discussions of the Web's
future, politicking regarding changes in the structure and
protocols of the web that affect both clients and servers, et
cetera.
comp.infosystems.www.announce
A moderated forum for the announcement of new and updated World
Wide Web resources and software.
comp.infosystems.www (DEFUNCT)
The old catch-all newsgroup, which may still exist on your
system but was officially removed on September 7th, 1994,
according to David Lawrence, moderator of
news.announce.newgroups. If your system still carries this
group, ask your administrator to remove it.
6.2: What mailing lists discuss the Web?
www-talk@info.cern.ch
Address: www-talk@info.cern.ch for CONTRIBUTIONS ONLY.
Administration: listserv@info.cern.ch (robot)
www-talk-request@info.cern.ch (human). Description: Technical
discussion, W3 related. Experts to experts. General questions
to the newsgroups, please. Archive: Not currently served, but
kept.
www-announce@info.cern.ch
Address: www-announce@info.cern.ch. NOT FOR GENERAL USE -
serious low-volume announcements only. Administration:
listserv@info.cern.ch (robot),
www-announce-request@info.cern.ch (human). Description: Low
volume summary announcemements of product releases, etc.
Archive: Not currently public.
7: I WANT TO KNOW MORE
To find out more, use the web. This FAQ hopefully provides enough
information for you to locate and install a browser on your system. If
you have system specific questions regarding FTP, networking and the
like, please consult newsgroups relevant to your particular hardware
and operating system!
Once you're up and running, you may wish to consult the World Wide Web
Primer by Nathan Torkington. It is available at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-primer.html .
Later you may return to this FAQ for answers to some of the more
advanced questions. I encourage you to check out the changes listed
early in the document each time the FAQ appears.
8: CREDITS
Maintainer (11/93 to present): Thomas Boutell, boutell@netcom.com
Former Maintainer (until 11/93): Nathan Torkington,
Nathan.Torkington@vuw.ac.nz
archive.]
Archive-name: www/faq/part1
Last-modified: 1995/26/1
WORLD WIDE WEB FREQUENTLY ASKED QUESTIONS
This is part 1 of a 2-part posting.
Part 2 begins with section 5 (providing
information to the web). It should be the next
posting in this thread.
This document resides on the World Wide Web on Sunsite (URL is
http://sunsite.unc.edu/boutell/faq/www_faq.html ).
If you are unfamiliar with the term "URL", read on and learn!
Last update: 1/26/95
Contents
* 1: Recent changes to the FAQ
* 2: Information about this document
* 3: Elementary Questions
+ 3.1: What are WWW, hypertext and hypermedia?
+ 3.2: What is a URL?
+ 3.3: What are SGML and HTML?
+ 3.4: How does WWW compare to gopher and WAIS?
+ 3.5: Are there books about the web?
* 4: Accessing the Web (User Questions)
+ 4.1: Introduction: How can I access the web? (Even by email!)
+ 4.2: Browsers Accessible by Telnet
+ 4.3: Obtaining browsers
o 4.3.1: MS Windows, IBM OS/2 and MS Windows NT browsers
o 4.3.2: MSDOS browsers
o 4.3.3: Macintosh browsers
o 4.3.4: Amiga browsers
o 4.3.5: NeXTStep browsers
o 4.3.6: X/DecWindows (graphical UNIX, VMS) browsers
o 4.3.7: Text-based Unix and VMS browsers
o 4.3.8: VM/CMS browsers
o 4.3.9: Batch-mode "browsers"
+ 4.4: How can I access the web through a firewall?
+ 4.5: What is on the web?
o 4.5.1: How do I find out what's new on the web?
o 4.5.2: Where is the subject catalog of the web?
o 4.5.3: How can I search through ALL web sites?
+ 4.6: How can I save an inline image to disk?
+ 4.7: How can I get sound from the PC speaker with WinMosaic?
+ 4.8: I have a Windows PC (or a Macintosh). Why can't I open
WAIS URLs?
+ 4.9: I'm running XMosaic. Why can't I get external viewers
working?
+ 4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?
+ 4.11: How do I send newsgroup posts in HTML to my web client?
+ 4.12: I can't get SLIP. I want Mosaic. Is there a way? (YES!)
* 5: Providing Information to the Web (Provider Questions)
+ 5.1: How can I provide information to the web?
+ 5.2: Obtaining Servers
o 5.2.1: Unix Servers
o 5.2.2: Macintosh Servers
o 5.2.3: MS Windows, IBM OS/2 and MS Windows NT Servers
o 5.2.4: MSDOS and Novell Netware Servers
o 5.2.5: VMS Servers
o 5.2.6: Amiga Servers
o 5.2.7: VM/CMS Servers
o 5.2.8: Yeah, but which is best?
+ 5.3: Producing HTML documents
o 5.3.1: Writing HTML directly
o 5.3.2: HTML editors
o 5.3.3: Converting other formats to HTML
o 5.3.4: Checking your HTML for errors
+ 5.4: How do I publicize my work?
+ 5.5: Can I buy space on an existing server?
+ 5.6: How fast does my net connection have to be?
+ 5.7: Advanced Provider Questions
o 5.7.1: How do I set up a clickable image map?
o 5.7.2: How do I make a "link" that doesn't load a new
page?
o 5.7.3: Where can I learn how to create fill-out forms?
# 5.7.3.1: How can I create hidden fields in forms
(keeping state)?
# 5.7.3.2: How can users email me through their
browsers?
o 5.7.4: How do I comment an HTML document?
o 5.7.5: How can I create decent-looking tables and stop
using <PRE>...</PRE>?
o 5.7.6: What is HTML Level 3 and where can I learn more
about it?
o 5.7.7: How can I make interlaced and transparent GIFs?
And what are they?
o 5.7.8: How come mailto: URLs don't work?
o 5.7.9: How can I restrict and control access to my
server?
o 5.7.10: Which format is better for WWW images, JPEG or
GIF?
o 5.7.11: How can I mirror part of another server?
o 5.7.12: How can I keep robots off my server?
o 5.7.13: How can I keep statistics about my web site?
o 5.7.14: How can I generate web pages on the fly from a
program?
# 5.7.14.1: How can I generate GIF images on the fly
from my CGI programs?
* 6: Where can I discuss the Web?
+ 6.1: USENET Newsgroups
+ 6.2: Mailing Lists
* 7: I want to know more.
* 8: Credits
1: RECENT ADDITIONS AND CHANGES TO THE FAQ
* Added htmlchek to validation section
* Added information on interlaced GIFs
* Added information on the WN Server
* Added information on CGI script authoring
* Added information on the gd GIF-generating library
* Updated email links section
* More books!
* Slipknot section updated
* GLACI-HTTPD, a WWW server for Novell Netware
* WWW mailing lists section
* Updated URL for Gabriel White's HTML editor reviews
* IBM OS/2 WebExplorer
* MapMaker: From xv's Visual Schnauzer to an imagemap
* Added comp.infosystems.www.announce
* Added the Arena browser
2: INFORMATION ABOUT THIS DOCUMENT
This is an introduction to the World Wide Web project, describing the
concepts, software and access methods. It is aimed at people who know
a little about navigating the Internet, but want to know more about
WWW specifically. If you don't think you are up to this level, try an
introductory Internet book such as Ed Krol's "The Whole Internet" or
"EFF's Guide to the Internet". The latter is available electronically
by anonymous FTP from ftp.eff.org in the directory
pub/Net_info/EFF_Net_Guide.
This informational document is posted to news.answers,
comp.infosystems.www.users, comp.infosystems.www.providers,
comp.infosystems.www.announce, comp.infosystems.www.misc,
comp.infosystems.gopher, comp.infosystems.wais and alt.hypertext every
four days (please allow a day or two for it to propagate to your
site). The latest and best version is always available on the web as
http://sunsite.unc.edu/boutell/faq/www_faq.html , and is mirrored in
Japan (URL is
http://www.glocom.ac.jp/mirror/sunsite.unc.edu/boutell/faq/www_faq.htm
l ). (see section 3.2, "What is a URL?" to understand what this term
means.) If you run a mirror site which automatically mirrors this
document, please submit the URL for inclusion in the list of mirrors.
Thanks to both Sunsite and Glocom.
This document is also available by anonymous FTP from ftp.netcom.com
in the directory pub/bo/boutell/faq.
In addition, the most recently posted version of this document is kept
on the news.answers archive on rtfm.mit.edu in
/pub/usenet/news.answers/www/faq. For information on FTP, send e-mail
to mail-server@rtfm.mit.edu with:
send usenet/news.answers/finding-sources
in the body (not subject line) of your message, instead of asking me.
If you want the HTML version but are located behind a firewall, you
can acquire it from CERN's WWW email server. Send mail to
listproc@www0.cern.ch with the following single line in the body
(leave the subject blank):
source http://sunsite.unc.edu/boutell/faq/www_faq.html
Thomas Boutell maintains this document. Feedback about it is to be
sent via e-mail to boutell@netcom.com.
In all cases, regard this document as out of date. Definitive
information should be on the web, and static versions such as this
should be considered unreliable at best. The most up-to-date version
of the FAQ is the version maintained on the web. Please excuse any
formatting inconsistencies in the posted version of this document, as
it is automatically generated from the on-line version.
3: ELEMENTARY QUESTIONS
3.1: What are WWW, hypertext and hypermedia?
WWW stands for "World Wide Web". The WWW project, started by CERN (the
European Laboratory for Particle Physics), seeks to build a
distributed hypermedia system.
The advantage of hypertext is that in a hypertext document, if you
want more information about a particular subject mentioned, you can
usually "just click on it" to read further detail. In fact, documents
can be and often are linked to other documents by completely different
authors -- much like footnoting, but you can get the referenced
document instantly!
To access the web, you run a browser program. The browser reads
documents, and can fetch documents from other sources. Information
providers set up hypermedia servers which browsers can get documents
from.
The browsers can, in addition, access files by FTP, NNTP (the Internet
news protocol), gopher and an ever-increasing range of other methods.
On top of these, if the server has search capabilities, the browsers
will permit searches of documents and databases.
The documents that the browsers display are hypertext documents.
Hypertext is text with pointers to other text. The browsers let you
deal with the pointers in a transparent way -- select the pointer, and
you are presented with the text that is pointed to.
Hypermedia is a superset of hypertext -- it is any medium with
pointers to other media. This means that browsers might not display a
text file, but might display images or sound or animations.
3.2: What is a URL?
URL stands for "Uniform Resource Locator". It is a draft standard for
specifying an object on the Internet, such as a file or newsgroup.
URLs look like this: (file: and ftp: URLs are synonymous.)
* file://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip
* ftp://wuarchive.wustl.edu/mirrors
* http://info.cern.ch:80/default.html
* news:alt.hypertext
* telnet://dra.com
The first part of the URL, before the colon, specifies the access
method. The part of the URL after the colon is interpreted specific to
the access method. In general, two slashes after the colon indicate a
machine name (machine:port is also valid).
When you are told to "check out this URL", what to do next depends on
your browser; please check the help for your particular browser. For
the line-mode browser at CERN, which you will quite possibly use first
via telnet, the command to try a URL is "GO URL" (substitute the
actual URL of course). In Lynx you just select the "GO" link on the
first page you see; in graphical browsers, there's usually an "Open
URL" option in the menus.
3.3: What are SGML and HTML?
Documents on the World Wide Web are written in a simple "markup
language" called HTML, which stands for Hypertext Markup Language. See
section 5.3 for more information about creating HTML documents for use
on the web.
SGML is a much broader language which is used to define particular
markup languages for particular purposes. HTML is just a specific
application of SGML. You can learn more about SGML, and the rationale
behind HTML, by reading A Gentle Introduction to SGML (URL is
http://etext.virginia.edu/bin/tei-tocs?div=DIV1%26id=SG ), a document
provided by the Text Encoding Initiative. (Note: Some browsers
apparently crash on this URL. There's nothing wrong with the document;
try another browser if you have problems.)
3.4: How does WWW compare to gopher and WAIS?
While all three of these information presentation systems are
client-server based, they differ in terms of their model of data. In
gopher, data is either a menu, a document, an index or a telnet
connection. In WAIS, everything is an index and everything that is
returned from the index is a document. In WWW, everything is a
(possibly) hypertext document which may be searchable.
In practice, this means that WWW can represent the gopher (a menu is a
list of links, a gopher document is a hypertext document without
links, searches are the same, telnet sessions are the same) and WAIS
(a WAIS index is a searchable page, returning a document with no
links) data models as well as providing extra functionality.
World Wide Web usage grew far beyond Gopher usage in the last few
months, according to the statistics-keepers of the Internet backbone.
(Of course, World Wide Web browsers can also access Gopher servers,
which inflates the numbers for the latter.) WWW has long since reached
critical mass, with new commercial and noncommercial sites appearing
daily.
3.5: Are there books about the web?
Yes, quite a few. A brief list follows. New entries are solicited.
Please include ISBN numbers and/or ordering information.
The Mosaic Handbook (Mac, Windows and X editions)
From O'Reilly. A short, sweet guide to the World Wide Web from
a Mosaic user's perspective. Mac and Windows versions Include
Enhanced NCSA Mosaic on floppy disk; the X Window System
version includes NCSA Mosaic on CD-ROM. Telnet or gopher to
gopher.ora.com (log in as gopher) or find details on the web
(URL is http://gnn.com/ora/ ). Wherever fine X Window System
books and Nutshell Guides are sold.
The World Wide Web Unleashed
From Sams Publishing. By John December and Neil Randall.
Additional chapters contributed by others; I wrote the chapter
on HTML editors and filters. Covers both user and provider
issues in detail. Supporting pages available on the web (URL is
http://www.rpi.edu/~decemj/works/wwwu.html ). 1057 pages. ISBN:
0-672-30617-4. Call 1-800-428-5331 or +1-317-581-3500 for
ordering information.
Spinning the Web: How to Provide Information on the Internet
From Van Nostrand Reinhold. By Andrew Ford. Oriented toward
those with an interest in putting their data on the web. ISBN:
1-850-32141-8 (New York), 0-442-01962-9 (London). Available in
December 1994.
Teach Yourself Web Publishing with HTML in a Week
From Sams Publishing. By Laura Lemay. Also oriented toward
those who plan to publish materials on the web. ISBN:
0-672-30667-0. 400 pages. Includes information on setting up
servers and handling forms results as well as HTML writing and
editing. (URL is: http://slack.lne.com/lemay/theBook/index.html
) Available December 22nd, 1994. Call 1-800-428-5331 or
+1-317-581-3500 for ordering information.
The HTML Manual of Style
From Ziff-Davis Press. By Larry Aronson. Chapters: introduction
to the WWW, the HTML language, writing HTML documents, and HTML
examples. 120 pages. Available in December 1994.
The Internet via Mosaic and World-Wide Web
From Ziff-Davis Press. By Steve Browne. Details on obtaining
Mosaic and Trumpet Winsock, getting it all set up, and what to
do with it once it works. A chapter of interesting sites on the
Web as well. ISBN: 1-56276-259-1.
MOSAIC Quick Tour
From Ventana Press. By Gareth Branwyn. A good guide to
installing and using NCSA Mosaic under Windows. Includes basic
HTML and trouble-shooting chapters. "More hand-holding than the
FAQ and gives lots of details." - Mari J. Stoddard
Managing Internet Information Services
From O'Reilly and Associates. By Cricket Liu, Jerry Peek, Russ
Jones, Bryan Buus & Adrian Nye. A good choice for those who
will be installing and maintaining WWW servers; also includes
documentation on HTML, imagemaps and the like. Also covers
other types of Internet services.
Hands-On Mosaic: A Guide for Window Users
From Prentice Hall. By Dr. David Sachs & Henry Stair. ISBN:
0-13-172321-9.
HTML Authoring for Fun & Profit
From Prentice Hall. By Mary Morris. Jan 1995. ISBN:
0-13-359290-1.
NCSA Mosaic Handbook
From Prentice Hall. By Amy K. Kreiling & Frank Baker. Jan 1995.
ISBN: 0-13-196692-8.
Plug-n-Play Mosaic for Windows
From Sams. By Angela Gunn. ISBN 0-672-30627-1. 300 pages. Disks
include a special version of Enhanced NCSA Mosaic for Windows
with built-in TCP/IP Winsock and dialer, and an automated
configuration program (hence "plug-n-play"). The book is an
introduction to Mosaic and the Web with some coverage of
creating a home page and HTML and, of course, the obligatory
directory of Web sites.
Using Mosaic
From Que. Ed. by Que Development Group. ISBN: 0-7897-0021-2.
Covers NCSA Mosaic for Windows and the Macintosh.
Using the World Wide Web
From Que. Ed. by Que Development Group. ISBN: 0-7897-0016-6.
Mosaic User's Guide
From MIS Press. By Bryan Pfaffenberger. ISBN: 1-55828-409-5.
Using Mosaic for Windows
From Electric Avenue Press. By Stephen Gauer. ISBN:
0-969-8853-0-X.
4.1: Introduction: how can I access the web?
You have three options: use a browser on your own machine (the best
option), use a browser that can be telnetted to (not as good), or
access the web by email (the least attractive, but for some it's the
only way). It is always best to run a browser on your own machine,
unless you absolutely cannot do so; but feel free to telnet to a
browser for your first look at the web, or use email if the telnet
command does not work on your system (try it first!). Note that
"your machine" can be defined as a system you dial into from home,
such as netcom or another account provider. Running a text-based
browser on such a system is still preferable to telnetting to a
faraway site.
The following sections cover telnetting to a browser and obtaining
your own browser; if neither of these are possible for you (because
you have only an email-and-news connection to the Internet), here is
how to access a web page by email:
Send email to server@mail.w3.org (preferred) or to
listserv@info.cern.ch (older address if the first fails) containing
the following single line. (What you put on the subject line doesn't
matter; blank is OK. This line should go in the text of the message.)
You will receive as a reply a simple page intended to help you learn
more about the Web.
send http://www.earn.net/gnrt/www.html
4.2: Browsers accessible by telnet
An up-to-date list of these is available on the Web as
http://info.cern.ch/hypertext/WWW/FAQ/Bootstrap.html and should be
regarded as an authoritative list.
telnet.w3.org
A telnettable browser provided by the W3 coalition.
www.cc.ukans.edu
Offers Lynx, a full screen browser which requires a vt100
terminal. Log in as www. Does not allow users to "go" to
arbitrary URLs, so GET YOUR OWN COPY of Lynx and install it on
your system if your administrator has not done so already. The
best plain-text browser, so move mountains if necessary to get
your own copy of Lynx!
www.njit.edu
(or telnet 128.235.163.2) Log in as www. A full-screen browser
in New Jersey Institute of Technology. USA.
www.huji.ac.il
A dual-language Hebrew/English database, with links to the rest
of the world. The line mode browser, plus extra features. Log
in as www. Hebrew University of Jerusalem, Israel.
sun.uakom.cs
Slovakia. Has a slow link, only use from nearby.
info.funet.fi
(or telnet 128.214.6.102). Log in as www. Offers several
browsers, including Lynx (goto option is disabled there also).
fserv.kfki.hu
Hungary. Has slow link, use from nearby. Login is as www.
4.3: Obtaining browsers
The preferred method of access of the Web is to run a browser
yourself. Browsers are available for many platforms, both in source
and executable forms. Here is a list generated from the authoritative
list, http://info.cern.ch/hypertext/WWW/Clients.html .
4.3.1: MICROSOFT WINDOWS BROWSERS
NOTE: Most of these browsers require that you have SLIP, PPP or other
TCP/IP networking on your PC. The sole exception is SlipKnot, which
has limited features but operates well without a proper Internet
connection. SLIP or PPP can be accomplished over phone lines. You can
do this one of two ways: using a proper SLIP account, which requires
the active cooperation of your network provider or educational
institution, or using The Internet Adapter (section 4.12), a product
which simulates SLIP through your dialup Unix shell account. If you
only have non-Unix based dialup shell access, or have no PC at home,
your best option at this time is to run Lynx on the VMS (or Unix,
or...) system you call, or telnet to a browser if you cannot do so.
Cello Browser from Cornell LII. Available by anonymous FTP from
ftp.law.cornell.edu in the directory /pub/LII/cello.
Mosaic for Windows
From NCSA. Available by anonymous FTP from ftp.ncsa.uiuc.edu in
the directory PC/Windows/Mosaic.
WinWeb
From EINet. Available by anonymous FTP from ftp.einet.net in
the directory /einet/pc/winweb as the file winweb.zip.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but can
be evaluated free of charge for an unlimited period of time by
individuals. Netscape supports some of the official extended
HTML tags as well as its own variations. The 16-bit version
works under both OS/2 and Windows. Available by anonymous FTP
from the following sites (use the mirror closest to you; see
the URL above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Spry Mosaic
From Spry. Available by anonymous FTP from ftp.spry.com in the
directory AirMosaicDemo as the file AMOSDEMO.EXE. Spry Mosaic
is a commercial product but a demonstration version is
available and can be registered inexpensively. Works under
Windows and OS/2. Supports the mailto: URL, transparent GIFs,
ALT tags, hierarchical hotlists, etc.
Booklink
From Booklink. Available by anonymous FTP from ftp.booklink.com
in the directory lite; this is a demonstration version of the
full browser, which costs $99. Booklink can open many
simultaneous connections in different windows and display
images and pages progressively; at the time of this writing it
is the only browser to equal Netscape in this area. The "lite"
version can only open two simultaneous connections, however.
SlipKnot
SlipKnot is the only graphical WWW browser that operates
entirely without SLIP, PPP, an Ethernet connection, or special
server-side software (but consider TIA, section 4.12 for
another workaround). SlipKnot supports multiple fonts, inline
images, and review of documents you have already received while
new documents arrive, and it operates entirely through your
regular Unix shell account. SlipKnot does not require that
you install any new software on your Unix shell account.
(However, it is lacking certain important features as a result,
such as forms and validation; this will keep you from accessing
some web pages. SlipKnot does support the <ISINDEX> tag, which
many sites support as a simpler alternative to forms.) You can
obtain SlipKnot by anonymous FTP from ftp.netcom.com in the
directory pub/pbrooks/slipknot or from oak.oakland.edu in the
directory SimTel/win3/internet. For more information, see the
SlipKnot information page (URL is
http://www.interport.net/slipknot/slipknot.html ) or send a
blank email message to slipknot@micromind.com.
IBM OS/2 WebExplorer
A native IBM OS/2 web browser. WebExplorer is a multithreaded
application and replaces the usual "back" and "forward" buttons
with a visual map of your exploration of the web. IBM
WebExplorer can be acquired by anonymous FTP from
ftp01.ny.us.ibm.net in the directory pub/WebExplorer/ .
4.3.2: MSDOS BROWSERS
NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
networking on your PC. SLIP or PPP can be accomplished over phone
lines. You can do this one of two ways: using a proper SLIP account,
which requires the active cooperation of your network provider or
educational institution, or using The Internet Adapter (section 4.12),
a product which simulates SLIP through your dialup Unix shell account.
If you only have non-Unix based dialup shell access, or have no PC at
home, your best option at this time is to run Lynx on the VMS (or
Unix, or...) system you call, or telnet to a browser if you cannot do
so.
DosLynx
DosLynx is an excellent text-based browser for use on DOS
systems. You must have a level 1 packet driver, or an emulation
thereof, or you will only be able to browse local files;
essentially, if your PC has an Ethernet connection, or you have
SLIP, you should be able to use it. DosLynx can view GIF
images, but not when they are inline images (as of this
writing). See the README.HTM file at the DosLynx site for
details. You can obtain DosLynx by anonymous FTP from
ftp2.cc.ukans.edu in the directory pub/WWW/DosLynx; the URL is
ftp://ftp2.cc.ukans.edu/pub/WWW/DosLynx/.
4.3.3: MACINTOSH BROWSERS
NOTE: These browsers require that you have SLIP, PPP or other TCP/IP
networking on your PC. SLIP or PPP can be accomplished over phone
lines. You can do this one of two ways: using a proper SLIP account,
which requires the active cooperation of your network provider or
educational institution, or using The Internet Adapter (section 4.12),
a product which simulates SLIP through your dialup Unix shell account.
If you only have non-Unix based dialup shell access, or have no PC at
home, your best option at this time is to run Lynx on the VMS (or
Unix, or...) system you call, or telnet to a browser if you cannot do
so.
Mosaic for Macintosh
From NCSA. Full featured. Available by anonymous FTP from
ftp.ncsa.uiuc.edu in the directory Mac/Mosaic.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but is
free for personal use by individuals. Version 0.9 (available to
the public as of this writing) does not support printing, but
this is promised in the forthcoming version 1.0. Contrary to
popular myth, version 1.0 will be free for personal use, just
like version 0.9. Available by anonymous FTP from the
following sites (use the mirror closest to you; see the URL
above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Samba From CERN. Basic. Available by anonymous FTP from info.cern.ch
in the directory /ftp/pub/www/bin as the file mac.
MacWeb
From EINet. Has features that Mosaic lacks; lacks some features
that Mosaic has. Available by anonymous FTP from ftp.einet.net
in the directory einet/mac/macweb.
4.3.4: AMIGA BROWSERS
AMosaic
Browser for AmigaOS, based on NCSA's Mosaic. Supports older
Amigas as well as the newer machines in the latest versions;
available for anonymous ftp from max.physics.sunysb.edu in the
directory /pub/amosaic, or from aminet sites in
/pub/aminet/comm/net. see the site for details. See the URL
http://insti.physics.sunysb.edu/AMosaic/home.html .
Emacs-W3
The Emacs-W3 browser works under Gnu Emacs on the Amiga (see
section 4.3.7).
4.3.5: NEXTSTEP BROWSERS
Note: NeXTStep systems can also run X-based browsers using one of the
widely used X server products for the NeXT. The browsers listed here,
by contrast, are native NeXTStep applications.
SpiderWoman
A brand-new (as of 12/94), multithreaded, graphical browser for
NeXTStep. Available by anonymous FTP from sente.epfl.ch in the
directory pub/software.
OmniWeb
A World Wide Web browser for NeXTStep. The URL for more
information is http://www.omnigroup.com/; you can ftp the
package from ftp.omnigroup.com in the /pub/software/ directory.
WorldWideWeb, CERN's NeXT Browser-Editor
A browser/editor for NeXTStep. Currently out of date; editor
not operational. Allows wysiwyg hypertext editing. Requires
NeXTStep 3.0. Available for anonymous FTP from info.cern.ch in
the directory /pub/www/src.
4.3.6: X/DECWINDOWS (GRAPHICAL UNIX, VMS) BROWSERS
NCSA Mosaic for X
Unix browser using X11/Motif. The original multimedia browser.
Full http 1.0 support including PUT-method forms, image maps,
etc. Recent beta versions have limited support for tables.
Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
directory Mosaic.
NCSA Mosaic for VMS
Browser using X11/DecWindows/Motif. For the VMS operating
system. Full http 1.0 support including PUT-method forms, image
maps, etc. Probably the best browser available for VMS.
Available by anonymous FTP from ftp.ncsa.uiuc.edu in the
directory Mosaic.
Netscape
From Mosaic Communications Corp (URL is:
http://home.mcom.com/info/index.html ). Downloads and displays
images incrementally while you read pages, which also display
incrementally, making it the best browser at the time of this
writing for those who connect to the web via modems. Also
supports many extensions to HTML, although not all conform to
the proposed standard. Netscape is a commercial product but is
free for personal use by individuals. Version 0.9 (available to
the public as of this writing) does not support printing, but
this is promised in the forthcoming version 1.0. Contrary to
popular myth, version 1.0 will be free for personal use, just
like version 0.9. Available by anonymous FTP from the
following sites (use the mirror closest to you; see the URL
above for the latest list):
+ ftp://ftp.mcom.com/netscape/
+ ftp://ftp.uu.net/networking/info-service/www/mcc/
+ ftp://ftp.digital.com/pub/net/infosys/Mosaic_Comm/Netscape/
+ ftp://ftp.icsi.net/pub/packages/netscape/
+ ftp://www.sandia.gov/Netscape/
+ ftp://lark.cc.ukans.edu/Netscape/
+ ftp://www.jsc.nasa.gov/pub/netscape/
+ ftp://ftp.meer.net/pub/Netscape/
+ ftp://src.doc.ic.ac.uk/packages/Netscape/
Quadralay GWHIS Viewer (Commercial Mosaic)
Quadralay offers a commercial-grade (not free!) version of
Mosaic for Unix systems, with Windows and Macintosh versions
expected in the future. (URL is:
http://www.quadralay.com/products/products.html#gwhis )
tkWWW Browser/Editor for X11
Unix Browser/Editor for X11. (Beta test version.) Available for
anonymous ftp from harbor.ecn.purdue.edu in the directory
tkwww[extension] (followed by an extension possibly dependent
on the current version). Please ftp to the site and look for
the latest version (or use the link above). Supports WSYIWYG
HTML editing.
MidasWWW Browser
A Unix/X browser from Tony Johnson. (Beta, works well.)
Viola for X (Beta)
Viola has two versions for Unix/X: one using Motif, one using
Xlib (no Motif). Handles HTML Level 3 forms and tables. Has
extensions for multiple columning, collapsible/expandable list,
client-side document include. Available by anonymous FTP from
ora.com in /pub/www/viola. More information available at the
URL http://xcf.berkeley.edu/ht/projects/viola/README.
Chimera
Unix/X Browser using Athena (doesn't require Motif). Supports
forms, inline images, etc.; closest to Mosaic in feel of the
non-Motif X11 browsers. Available for anonymous FTP from
ftp.cs.unlv.edu in the directory /pub/chimera.
Emacs w3 mode
The Emacs w3 mode supports multiple fonts, color, inline
images, movies, and the whole nine yards when run under a
graphical version of emacs; see section 4.3.7.
Arena Arena's primary purpose is to be a testbed for HTML Level 3
documents. As a result, Arena supports many of the new and
interesting features of HTML Level 3. As of this writing it is
still in prerelease and expectations should be set accordingly!
Available by anonymous FTP from ftp.w3.org in the directory
pub/www/arena/ .
4.3.7: Text-mode Unix and VMS browsers
These are text-based browsers for Unix (and in some cases also VMS)
systems. In many cases your system administrator will have already
installed one or more of these packages; check before compiling your
own copy.
Line Mode Browser
This program gives W3 readership to anyone with a dumb
terminal. A general purpose information retrieval tool.
Available by anonymous ftp from info.cern.ch in the directory
/pub/www/src.
The "Lynx" full screen browser
This is a hypertext browser for vt100s using full screen, arrow
keys, highlighting, etc. Available by anonymous FTP from
ftp2.cc.ukans.edu.
Tom Fine's perlWWW
A tty-based browser written in perl. Available by anonymous FTP
from archive.cis.ohio-state.edu in the directory pub/w3browser
as the file w3browser-0.1.shar.
For VMS
Dudu Rashty's full screen client based on VMS's SMG screen
management routines. Available by anonymous FTP from
vms.huji.ac.il in the directory www/www_client.
Emacs w3-mode
A WWW browser for emacs. Runs under Xwindows, NeXTstep, VMS,
OS/2, Windows NT, Windows 3.1, AmigaDOS, or just about any Unix
system. Also has fonts, color, inline images, and mouse support
if using Lemacs, Epoch, or Emacs 19. Also works in local mode
under DOS and on the Macintosh. Available by anonymous ftp from
ftp.cs.indiana.edu in the directory pub/elisp/w3.
4.3.8: VM/CMS BROWSERS
Albert
A WWW browser for the VM/CMS operating system. Available by
anonymous FTP from gopher.ufl.edu in the directory pub/vm/www/.
4.3.9: BATCH-MODE "BROWSERS"
Batch mode browser
A batch-mode "browser", url_get, which is available through the
URL http://www.utexas.edu/~zippy/url_get.html . It can be
retrieved via anonymous FTP to ftp.cc.utexas.edu, as the file
/pub/zippy/url_get.tar.Z. This package is intended for use in
cron jobs and other settings in which fetching a page in a
command-line fashion is useful.
4.4: How can I access the web through a firewall?
A "proxy server" is a specialized HTTP server which (typically) runs
on a firewall machine, providing access to the outside world for
people inside the firewall. The CERN httpd can be configured to run as
a proxy. Furthermore, it is able to perform caching of documents,
resulting in faster response times.
If you cannot arrange to run a proxy server (definitely the
recommended approach), read on:
For information on using NCSA Mosaic from behind a firewall, please
read the following. In general, browsers can be made useful behind
firewalls through the use of a package called "SOCKS"; the source must
be modified slightly and rebuilt to accommodate this. Whenever
possible, work with your network administrators to solve the
problem, not against them.
An excerpt from the NCSA Mosaic FAQ:
NCSA Mosaic requires a direct internet connection to work, but some
folks have put together a package that works behind firewalls. This is
completely unsupported by NCSA, but here is the latest announcement:
November 15, 1993: C&C Software Technology Center (CSTC) of NEC
Systems Lab has made available a version of SOCKS, a package for
running Internet clients from behind firewalls without breaching
security requirements, that includes a suitably modified version of
Mosaic for X 2.0. Beware: such a version is not supported by NCSA;
we can't help with questions or problems arising from the
modifications made by others. But, we encourage you to check it
out if it's interesting to you. Questions and problem notifications
can be sent to Ying-Da Lee (ylee@syl.dl.nec.com).
4.5: What is on the web?
Currently accessible through the web:
* anything served through gopher
* anything served through WAIS
* anything on an FTP site
* anything on Usenet
* anything accessible through telnet
* anything in hytelnet
* anything in hyper-g
* anything in techinfo
* anything in texinfo
* anything in the form of man pages
* sundry hypertext documents
4.5.1: HOW DO I FIND OUT WHAT'S NEW ON THE WEB?
comp.infosystems.www.announce
The newsgroup comp.infosystems.www.announce carries
announcements of new resources on the World Wide Web. Since
newsgroups are distributed, it can be accessed reliably even
when the net is very busy.
What's New With NCSA Mosaic
The unofficial newspaper of the World Wide Web is What's New
With NCSA Mosaic (URL is
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html )
, which carries announcements of new servers on the web and
also of new web-related tools. This should be in your hot list
if you're not using Mosaic (which can access it directly
through the help menu).
comp.internet.net-happinings
You can also check out the newsgroup
comp.internet.net-happenings, which carries WWW announcements
and many other Internet-related announcements.
4.5.2: WHERE IS THE SUBJECT CATALOG OF THE WEB?
There are several. There is no mechanism inherent in the web which
forces the creation of a single catalog (although there is work
underway on automatic mechanisms to catalog web sites). The best-known
catalog, and the first, is The WWW Virtual Library (URL is
http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html ),
maintained by CERN. The Virtual Library is a good place to find
resources on a particular subject, and has separate maintainers for
many subject areas.
There is also a newer cataloging system called ALIWEB that requires
very little effort to maintain and is growing rapidly (URL is
http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
4.5.3: HOW CAN I SEARCH THROUGH ALL WEB SITES?
Several people have written robots which create indexes of web sites
-- including sites which have not arranged to be mentioned in the
newspapers and catalogs above. (Before writing your own robot, please
read the section on robots.)
Here are a few such automatic indexes you can search:
* WebCrawler (URL is
http://webcrawler.cs.washington.edu/WebCrawler/WebQuery.html )
builds an impressively complete index; on the other hand, since it
indexes the content of documents, it may find many links that
aren't exactly what you had in mind. However, it does a good job
of sorting the documents it finds according to how closely they
match your search.
* World Wide Web Worm (URL is
http://www.cs.colorado.edu/home/mcbryan/WWWW.html ) builds its
index based on page titles and URL contents only. This is somewhat
less inclusive, but pages it finds are more likely to be an exact
match with your needs.
* Lycos (URL is http://fuzine.mt.cs.cmu.edu/mlm/lycos-home.html ) is
another web-indexing robot, which includes the ability to submit
the URLs of your own documents by hand, ensuring that they are
available for searching.
You can read about other robots in the robots section.
4.6: How can I save an inline image to disk?
Here are two ways:
1. Turn on "load to local disk" in your browser, if it has such an
option; then reload images. You'll be prompted for filenames instead
of seeing them on the screen. Be sure to shut it off when you're done
with it.
2. Choose "view source" and browse through the HTML source; find the
URL for the inline image of interest to you; copy and paste it into
the "Open URL" window. This should load it into your image viewer
instead, where you can save it and otherwise muck about with it.
4.7: How can I get sound from the PC speaker with WinMosaic?
This piece of wisdom donated by Hunter Monroe:
This section explains how to install sound on a PC which already has a
working version of Mosaic for Microsoft Windows. Be warned in advance
that the results may be poor.
To get Mosaic to produce sound out of the PC speaker, first, you need
a driver for the speaker. You can get the Microsoft speaker driver
from the URL ftp://ftp.microsoft.com/Softlib/MSLFILES/SPEAK.EXE or by
doing an Archie search to find it somewhere else. SPEAK.EXE is a
self-extracting file. Copy the speak.exe file to a new directory, and
then type "SPEAK" at the DOS prompt. Do not put the file SPEAKER.DRV
in a separate directory from OEMSETUP.INF.
Now, you need to install the driver. In Windows, from the Program
Manager choose successively Main/Control Panel/Drivers/Add/Unlisted or
updated drivers/(enter path of SPEAK.EXE)/PC Speaker. At this point
some strange sounds come out as the driver is initialized. Change the
settings to improve the sound quality on the various sounds: tada,
chimes, etc. Click OK when you are finished and choose the Restart
windows option.
Having installed the speaker driver, you will now get sounds whenever
you start Windows, make a mistake, or exit Windows. If you do not want
this, from the Main/Control Panel/Sounds menu, make sure there is no X
next to "Enable System Sounds."
Now, you need a sound viewer program that Mosaic can call to display
sounds. NCSA unfortunately recommend WHAM, which does not work well
with a PC speaker. Get the program WPLANY instead. You can find a copy
nearby with an Archie search on the string "wplny"; the current
version is WPLNY09B.ZIP. For details on archie and other basic issues
related to FTP, please read the Usenet newsgroup
news.announce.newusers.
Move the zip file to a new directory, and use an unzip program like
pkunzip to unzip it, producing the files WPLANY.EXE and WPLANY.DOC.
Then edit the MOSAIC.INI file to remove the "REM" before the line
"TYPE9=audio/basic". Then, you need lines in the section below that
read something like: audio/basic="c:\wplany\wplany.exe %ls"
audio/wav="c:\wplany\wplany.exe %ls" where you have filled in the
correct path for wplany.exe. The MOSAIC.INI file delivered with Mosaic
may have NOTEPAD.EXE on the audio/basic line, but this will not work.
Now, restart Mosaic, and you should now be able to produce sounds. To
check this, with Mosaic choose File/Local File/\WINDOWS\*.WAV and then
try to play TADA.WAV. Then, you might try the Mosaic Demo document for
some .AU sounds, but you are lucky if your speaker produces something
you can understand.
4.8: I have a Windows PC or Macintosh. Why can't I access WAIS URLs?
This answer provided by Michael Grady (m-grady@uiuc.edu):
The version of Mosaic for X has "wais client" code built-in to it.
This was relatively easy for the developers to do, because there was
already a set of library routines for talking to WAIS available for
Unix as "public domain" (freeWAIS). I don't think there is such a
library of routines for PC/Windows or Mac, which would make it much
more difficult for the Mosaic versions for Windows and the Mac to add
"wais client" capability. Therefore, at least for now, neither the
Windows or Mac versions of Mosaic support direct query of a WAIS
server (i.e. can act as wais clients themselves).
4.9: I'm running XMosaic. Why can't I get external viewers working...
... No matter what no matter what I do to my .mailcap and .mime.types
files?
Answer provided by Ronald E. Daniel (rdaniel@acl.lanl.gov):
Mosaic only looks at the .mime.types file if it has no idea what the
document's type is. This is actually a very rare situation.
Essentially all servers now use the HTTP/1.0 protocol, which means
that they tell Mosaic (or other browsers) what the document's MIME
Content-type is. The servers use a file very much like Mosaic's
.mime.types file to infer the Content-type from the filename's
extension.
It is pretty simple to find out if this really is the problem. Use
telnet to talk to the server and find out if it is assigning a MIME
type to the document in question. Here's an example, looking at the
home page for my server. (idaknow: is my shell prompt)
idaknow: telnet www.acl.lanl.gov 80 // Connect to the httpd server
Trying 128.165.148.3 ...
Connected to www.acl.lanl.gov.
Escape character is '^]'.
HEAD /Home.html HTTP/1.0 // replace Home.html with your
documen
t
// you supply the blank line
HTTP/1.0 200 OK // the rest of this comes from the
serve
r Date: Wednesday, 25-May-94 19:18:11 GMT
Server: NCSA/1.1
MIME-version: 1.0
Content-type: text/html // Here's the MIME Content-type
Last-modified: Monday, 16-May-94 16:21:58 GMT
Content-length: 1727
Connection closed by foreign host.
idaknow:
In the example above, /Home.html will get
http://www.acl.lanl.gov/Home.html .
Normally servers will be configured to supply a Content-type of
text/plain if they don't know what else to do. If this is the
problem you are having, take a look at the TypesConfig documentation
for NCSA's httpd. You can have the server look at the filename
extension, supply the correct Content-type, then use your local
.mailcap file to tell Mosaic what viewer to use to look at the
document.
Russ Segal adds:
The answer from Ronald Daniel is essentially correct, but it needs a
small addendum.
When starting Moasic, you can specify a "fileProxy" which will fetch
files for you:
"*fileProxy: http://socks/"
If you do this, file: URLs are no longer strictly local accesses. So
even if the URL is not fttp:, the proxy server must be upgraded as
Mr. Daniel suggests.
4.10: Hey, I know, I'll write a WWW-exploring robot! Why not?
Programs that automatically traverse the web can be quite useful, but
have the potential to make a serious mess of things. Robots have been
written which do a "breadth-first" search of the web, exploring many
sites in a gradual fashion instead of aggressively "rooting out" the
pages of one site at a time. Some of these robots now produce
excellent indexes of information available on the web.
But others have written simple depth-first searches which, at the
worst, can bring servers to their knees in minutes by recursively
downloading information from CGI script-based pages that contain an
infinite number of possible links. (Often robots can't realize this!)
Imagine what happens when a robot decides to "index" the CONTENTS of
several hundred mpeg movies. Shudder.
The moral: a robot that does what you want may already exist; if it
doesn't, please study the document World Wide Web Robots, Wanderers
and Spiders (URL is: http://web.nexor.co.uk/mak/doc/robots/robots.html
) and learn about the emerging standards for exclusion of robots from
areas in which they are not wanted. You can also read about existing
robots there.
4.11: How do I send newsgroup posts in HTML to my web client?
How to do this depends greatly on your system; if you have a Mac or
Windows system, the answer is completely different. But, as food for
thought, here is a simple shell script I use on my Unix account to
send posts from rn and related newsreaders to Lynx. Put this text in
the file "readwebpost" and use the "chmod" command to make it
executable, then put it somewhere in your path (such as your personal
bin directory):
#!/bin/sh
echo \<PRE\> > .article.html
cat >> .article.html
echo \</PRE\> >> .article.html
lynx .article.html < /dev/tty
rm .article.html
Then add the following line to your .rnmac file (create it if you
don't already have one):
W |readwebpost %C
Now, when you press "W" while reading a post in rn, a message will be
sent to Lynx, and the links enclosed in it will be live.
Larry W. Virden provides the following version which invokes Mosaic
instead, and is also capable of communicating with an already-running
copy of Mosaic instead of launching another. (You can use the same rn
macro as above, invoking "goto-xm" instead of "readwebpost".) Read the
comments for details on the assumptions made by the script.
#! /bin/sh
# goto-xm, by Joseph T. Buck <jbuck@eecs.berkeley.edu>
# Modified heavily by Larry W. Virden <lvirden@cas.org>
# Script for use with newsreaders such as trn. Piping the article
# through this command causes xmosaic to pop up, pointing to the
# article. If an existing xmosaic (version 1.1 or later) exists,
# the USR1 method will be used to cause it to point to the correct
# article, otherwise a new one will be started.
# assumptions: ps command works as is on SunOS 4.1.x, may need changes
# on other platforms.
URL=`/bin/grep '^Message-ID:' | /bin/sed -e 's/.*</news:/' -e 's/>.*//'`
if [ "X$URL" = "X" ]; then
echo "USAGE: $0 [goto] [once] < USENET_msg" >&2
exit 1
fi
pid=`ps -xc | egrep '[Mm]osaic' | awk 'NR == 1 {print $1}'`
p=`which Mosaic`
gfile=/tmp/Mosaic.$pid
$p "$URL" &
if [ "$#" -gt 0 ] ; then
if [ "$1" = "goto" -o "$1" = "same" ] ; then
shift
echo "goto" > $gfile
else
echo "newwin" > $gfile
fi
else
echo "newwin" > $gfile
fi
/bin/awk 'END { printf "'"$URL"'" }' </dev/null >> $gfile
trap "echo signal encountered" 30
kill -USR1 $pid
exit 0
See also MosaicMail (URL is
http://www.oac.uci.edu/indiv/ehood/mhonarc.doc.html ), a Perl script
which pipes email and/or news to your current Mosaic session.
4.12: I can't get SLIP. I want Mosaic. Is there a way?
YES! If you have a plain old Unix shell account on a Unix system, such
as a SunOS or Ultrix system, you can do one of two things: you can run
SlipKnot, a special browser which operates using programs that may
already be installed on your shell account (see section 4.3.1), or you
can run The Internet Adapter (TIA), a program which provides a
pseudo-SLIP connection. The remainder of this section focuses on TIA.
TIA is not free software, but there is a free two-week trial period
and it is very cheap to register.
"So what do I run on my machine at home?"
Exactly the same software you would use for real SLIP; as far as your
PC is concerned, it is a SLIP connection. If you're unfamiliar with
SLIP please check out a newsgroup relevant to your particular type of
PC (Windows, Mac, etc). (This isn't restricted to common systems;
because all the emulation happens on your Unix shell account, your
client machine can run anything that supports SLIP.)
"Details, please! I'm confused."
Check out the TIA home page (URL is
http://marketplace.com/tia/tiahome.html ), or send email to
info@marketplace.com and request details about TIA.
If you have a Macintosh, check out the Macintosh TIA Users' FAQ (URL
is: ftp://ftp.netcom.com/pub/bi/billa/tia/faq.html ) for additional
help.
Archive-name: www/faq/part2
Last-modified: 1995/26/1
5.1: HOW CAN I PROVIDE INFORMATION TO THE WEB?
Information providers run programs that the browsers can obtain
hypertext from. These programs can either be WWW servers that
understand the HyperText Transfer Protocol HTTP (best if you are
creating your information database from scratch), "gateway" programs
that convert an existing information format to hypertext, or a
non-HTTP server that WWW browsers can access -- anonymous FTP or
gopher, for example.
To learn more about World Wide Web servers, you can consult a www
server primer by Nathan Torkington, available at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-servers.html .
If you only want to provide information to local users, placing your
information in local files is also an option. This means, however,
that there can be no off-machine access.
5.2: Obtaining Servers
Servers are available for Unix, Macintosh, MS Windows, Windows NT,
OS/2, and VMS systems. If you know of a server for another operating
system, please contact me.
See http://info.cern.ch/hypertext/WWW/Daemon/Overview.html for more
information on writing servers and gateways in general.
5.2.1: UNIX SERVERS
NCSA httpd
NCSA has released a server, known as the NCSA httpd; it is
available at the URL ftp://ftp.ncsa.uiuc.edu/Web/ncsa_httpd .
EIT httpd
EIT has created the Webmaster's Starter Kit, which installs
their WWW server on your system via the web through a painless
forms interface. Recommended for those unfamiliar with server
installation. You can learn more about the starter kit and the
EIT httpd at the starter kit site (URL is
http://wsk.eit.com/wsk/doc/ ).
CERN httpd
CERN's server is available for anonymous FTP from info.cern.ch
(URL is http://info.cern.ch/hypertext/WWW/Daemon/Status.html )
and many other places. Use your local copy of archie to search
for "www" in order to find a nearby site.
GN Gopher/HTTP server
The GN server is unique in that it can serve both WWW and
Gopher clients (in their native modes). This is a good server
for those migrating from Gopher to WWW, although it does not
have the server-side-script capabilities of the NCSA and CERN
servers. See the URL http://hopf.math.nwu.edu/ .
Perl server
There is also a server written in the Perl scripting language,
called Plexus, for which documentation is available at the URL
http://bsdi.com/server/doc/plexus.html .
WN Server
The WN Server, available at the URL
http://hopf.math.nwu.edu/docs/manual.html , is designed with an
emphasis on security and flexibility, and takes a different
approach from the NCSA and CERN servers. It provides text
searching facilities as a standard feature.
5.2.2: MACINTOSH SERVERS
There is a server for the Macintosh, MacHTTP, available at the URL
http://www.uth.tmc.edu/mac_info/machttp_info.html .
5.2.3: MS WINDOWS, IBM OS/2 AND MS WINDOWS NT SERVERS
HTTPS (Windows NT)
HTTPS is a server for Windows NT systems, both Intel and Alpha
-- based. It is available via anonymous FTP from emwac.ed.ac.uk
in the directory pub/https (URL is
ftp://emwac.ed.ac.uk/pub/https). (Be sure to download the
version appropriate to your processor.) You can read a detailed
announcement at the FTP site, or by using the URL
ftp://emwac.ed.ac.uk/pub/https/https.txt.
A professional version is also available (URL is
http://emwac.ed.ac.uk/html/internet_toolchest/https/prof.htm ).
NCSA httpd for Windows
The NCSA httpd for Windows has most of the features of the Unix
version, including scripts (which generate pages on the fly
based on user input). It is available by anonymous FTP from the
ftp site ftp.alisa.com in the directory pub/win-httpd, and
documentation can be found at the URL
http://www.alisa.com/win-httpd/index.html .
SerWeb
A simple, effective server for Windows writtten by Gustavo
Estrella. Available by anonymous ftp from
winftp.cica.indiana.edu (or one of its mirror sites, such as
nic.switch.ch), as the file serweb03.zip, in the directory
/pub/pc/win3/winsock.
There is also a Windows NT version of SerWeb, available by
anonymous FTP from emwac.ed.ac.uk as /pub/serweb/serweb_i.zip.
WEB4HAM
Another Windows-based server, available by anonymous FTP from
ftp.informatik.uni-hamburg.de as /pub/net/winsock/web4ham.zip.
OS2HTTPD
An OS/2 server, written by Frankie Fan. See the home page (URL
is ftp://ftp.netcom.com/pub/kf/kfan/overview.html ) for
details, or fetch the package by anonymous FTP from
ftp.netcom.com in the directory pub/kf/kfan.
5.2.4: MSDOS AND NOVELL NETWARE SERVERS
KA9Q KA9Q NOS (nos11c.exe) is a internet server package for DOS that
includes HTTP and Gopher servers. It can be obtained via
anonymous FTP from one of the following sites:
inorganic5.chem.ufl.edu
biochemistry.cwru.edu
GLACI-HTTPD
GLACI-HTTPD is a Netware Loadable Module which allows a Novell
NetWare server to become a World Wide Web server (URL is
http://www.glaci.com/info/glaci-httpd.html ).
5.2.5: VMS SERVERS
CERN HTTP for VMS
A port of the CERN server to VMS. Available at the URL
http://delonline.cern.ch/disk$user/duns/doc/vms/distribution.html .
Region 6 Threaded HTTP Server
A native VMS server which uses DECthreads(tm). This is a
potentially major performance advantage because VMS has a high
overhead for each process, which is a problem for the
frequently-forking NCSA and CERN servers that began life under
Unix. A multithreaded server avoids this overhead. Available at
the URL http://kcgl1.eng.ohio-state.edu/www/doc/serverinfo.html .
5.2.6: AMIGA SERVERS
NCSA's Unix server has been ported to the Amiga, and is bundled with
the AMosaic browser. See the URL
http://insti.physics.sunysb.edu/AMosaic/home.html for details.
5.2.7: VM/CMS SERVERS
A VM/CMS web server is available; see the URL
http://ua1vm.ua.edu/~troth/rickvmsw/rickvmsw.html for more
information. If you don't yet have a web browser to try this URL with,
check out the VM/CMS Browsers section.
5.2.8: YEAH, BUT WHICH IS BEST?
To find out which server is best for your needs, you will want to
consult Paul Hoffman's Server Comparison Chart (URL is
http://sunsite.unc.edu/boutell/faq/chart.html ). That document is also
available by anonymous FTP from ftp.netcom.com in the directory
pub/bo/boutell/faq.
5.3: Producing HTML documents
HTML is the simple markup system used to create hypertext documents.
There are three ways to produce HTML documents: writing them yourself,
which is not a very difficult skill to acquire, using an HTML editor,
which assists in doing the above, and converting documents in other
formats to HTML. The following three sections cover these
possibilities in sequence.
5.3.1: WRITING HTML DOCUMENTS YOURSELF
You can write an HTML document with any text editor. Try the "source"
button of your browser (or "save as" HTML) to look at the HTML for a
page you find particularly interesting. The odds are that it will be a
great deal simpler than you would expect. If you're used to marking up
text in any way (even red-pencilling it), HTML should be rather
intuitive.
A beginner's guide to HTML is available at the URL
http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html . You
can also find a plain text version (at the URL
ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.txt) and a compressed
Postscript version (at the URL
ftp://ftp.ncsa.uiuc.edu/ncsapubs/WWW/HTMLPrimer.ps.Z). (Since the
latter two are FTP URLs, you can fetch them by hand using FTP if you
do not yet have a web browser.)
There is also an HTML primer by Nathan Torkington at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-html.html .
5.3.2: HTML EDITORS
Of course, most folks would still prefer to use a friendlier,
graphical editor. Some editors are WYSIWYG (What You See Is What You
Get), or close to it; others simply assist you in writing HTML by
plugging in the desired markup tags for you from a menu.
Fans of the EMACS editor can use EMACS and html-helper-mode , an EMACS
"mode" for HTML editing (URL is http://www.reed.edu/~nelson/tools/ ).
There is also another Emacs HTML mode, html-mode.el (URL is
ftp://ftp.ncsa.uiuc.edu/Web/html/elisp/html-mode.el ).
For Microsoft Windows users, there is an editor called HTML Assistant
with features to assist in the creation of HTML documents. It can be
had by anonymous FTP from ftp.cs.dal.ca in the directory /htmlasst/.
Read the README.1ST file in this directory for information on which
files to download.
ANT_HTML.DOT is a Word for Windows 6.0 template designed to convert
Word documents into HTML documents in a WYSIWYG environment. It
includes a demo version of the ANT_PLUS utility, which converts HTML
files to WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or
any other format possible in Word 6.0. Contact jswift@freenet.fsu.edu
if you need more information.
A WYSIWYG editor for the Web, SoftQuad HoTMetaL, is available for
downloading at NCSA and numerous other sites. Many mirror sites exist;
if you can't get through to one, try another, don't give up! That's
what mirror sites are for. (Also be sure to use the copy closest to
you geographically if possible.) Hotmetal is available for both Sun
Sparc systems and Windows systems; note that Windows users need at
least 6 megabytes of free memory. (A 2-megabyte swap file should just
barely do the trick on a 4MB machine.)
Known mirrors:
* ftp://ftp.ncsa.uiuc.edu/Web/html/hotmetal/
* ftp://ftp.ifi.uio.no/pub/SGML/HoTMetaL
* ftp://sgml1.ex.ac.uk/SoftQuad
* ftp://src.doc.ic.ac.uk/packages/WWW/ncsa/html/hotmetal/
*
ftp://askhp.ask.uni-karlsruhe.de/pub/infosystems/mosaic/contrib/Sof
tQuad
* ftp://ftp.cs.concordia.ca/pub/www
*
You need a Sun SPARC or Microsoft Windows system and 6MB of disk (6MB
of RAM minimum for MS Windows; swap files count). Other Unix systems
may be supported by the time you read this; have a look on one of the
sites above.
Because it is context-sensitive, HoTMetaL guides users in creating new
HTML documents and in cleaning up old ones. A Publish command changes
appropriate SRC and HREF attributes from local paths to http
locations. For more information, FTP the README file from the same
directory, or send email to hotmetal@sq.com. A HoTMetaL Pro
commercially supported version is available for purchase from SoftQuad
and its resellers.
Also see Gabriel White's reviews of MS Windows HTML editors (URL is
http://werple.mira.net.au/%7Egabriel/web/html/editors/ ). Another
option, if you have an SGML editor, is to use it with the HTML DTD
(URL is http://info.cern.ch/hypertext/WWW/MarkUp/DTDHeading.html ).
An editor for all X users: TkWWW (listed above under X browsers)
supports WYSIWYG HTML editing; and since it's a browser, you can try
out links immediately after creating them.
Another editor for X users: Phoenix (URL is
http://www.bsd.uchicago.edu/ftp/pub/phoenix/README.html ) is a fully
WYSIWYG HTML editor which insulates the user from direct control of
the HTML tags. Available by anonymous FTP from www.bsd.uchicago.edu in
the pub/phoenix subdirectory.
Also for X users, there is a package called htmltext which supports
WYSIWYG HTML editing. More information is available at the URL
http://web.cs.city.ac.uk/homes/njw/htmltext/htmltext.html .
For Macintosh users, there is a near-WYSIWYG package called HTML
Editor (URL is http://dragon.acadiau.ca:1667/~giles/HTML_Editor).
ANT_HTML is a Word for the Macintosh template designed to convert Word
documents into HTML documents in a WYSIWYG environment. It includes a
demo version of the ANT_PLUS utility, which converts HTML files to
WYSIWYG. ANT_PLUS also converts HTML files to ASCII, RTF, or any other
format possible in Word. At the time of this writing it was scheduled
to have been released on the Macintosh (it has long been available for
Windows). Contact jswift@freenet.fsu.edu for more information. Also
for Macintosh users, the BBEdit HTML extensions allow the BBEdit and
BBEdit Lite text editors for the Macintosh to conveniently edit HTML
documents. (URL is http://www.uji.es/bbedit-html-extensions.html .)
You can also obtain the extensions package by anonymous ftp from
sumex-aim.stanford.edu as info-mac/bbedit-html-ext-b3.hqx.
There is an alternative BBEdit extension package available as well
(URL is http://www.york.ac.uk/~ld11/BBEditTools.html ). it is
available by FTP from ftp.york.ac.uk in the directory
/pub/users/ld11/BBEdit_HTML_Tools.sea.hqx.
NCSA's List of Filters and Editors, for which the URL is
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/faq-software.html#ed
itors, mentions several editors, including two for MS Windows. In some
cases, the "editor" amounts to a set of macros for an existing word
processor, which can provide a near-WYSIWYG environment.
Note that this URL contains uppercase and lowercase letters; certain
operating systems won't allow mixed case on the command line, or will
only allow it if it is quoted (VMS), so if you are launching Lynx or
another client and specifying a URL at the command line, try quoting
the URL in double-quotes ("URL").
5.3.3: CONVERTING OTHER FORMATS TO HTML
There is a collection of filters for converting your existing
documents (in TeX and other non-HTML formats) into HTML automatically,
including filters that can allow more or less WYSIWYG editing using
various word processors:
Rich Brandwein and Mike Sendall's List at CERN (URL is
http://info.cern.ch/hypertext/WWW/Tools/Filters.html ).
(Note that this URL contains uppercase and lowercase letters; certain
operating systems such as VMS require you to quote mixed-case URLs
when launching a borwser from the command line. This is NOT a bug in
the browser.)
There is also a Word for Windows template for writing HTML documents,
available at the URL http://www.gatech.edu/word_html/release.htm .
5.3.4: CHECKING YOUR HTML FOR ERRORS
Tools to validate your HTML documents (check them for errors) are
available. There is a form at the URL
http://www.hal.com/%7Econnolly/html-test/service/validation-form.html
which will check HTML documents for errors according to the latest
specification; note that you are encouraged to set up the program on
your own system if you make heavy use of the form. There is also a
tool which will check the links in your documents for links to
nonexistent resources, such as pages that have moved (URL is
http://wsk.eit.com/wsk/dist/doc/admin/webtest/verify_links.html ).
Also try weblint (URL is
http://www.khoros.unm.edu/staff/neilb/weblint.html ), a Perl script
that checks your HTML for errors; you can even try it out over the web
through an HTML form. The script is available by anonymous FTP from
ftp.khoros.unm.edu in the directory pub/perl/www.
Another such tool is htmlchek (URL is:
http://uts.cc.utexas.edu/~churchh/htmlchek.html ), which checks HTML
documents for errors, creates a cross-reference, automatically expands
entities (such as European characters) to their proper HTML form, and
performs other useful services. htmlchek is available by anonymous FTP
from ftp.cs.buffalo.edu in the directory pub/htmlchek.
5.4: How do I publicize my work?
There are several things you can do to publicize your new HTML server
or other offering:
* Post to comp.infosystems.www.announce. PLEASE READ THE CHARTER
POSTING FIRST. In general, always read a newsgroup first to
familiarize yourself before posting to it.
* Submit it to the NCSA What's New Page at the URL
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/whats-new.html
(see the page for details on how to submit your listing!).
* Post it to the newsgroup comp.infosystems.announce. Please read
the group first to get a feel for the contents. You should not
post to comp.infosystems.www.users,.misc,.providers, etc., but if
you feel compelled to do so, please choose .misc as announcements
are of interest to both providers and users (and those who wear
both hats).
* Submit it to the maintainers of various catalogs, such as the WWW
Virtual Library (at the URL
http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html
) and the ALIWEB index (at the URL
http://web.nexor.co.uk/aliweb/doc/aliweb.html ).
* Read Gareth Rees' guide to publishing on the World Wide Web. (URL
is http://www.cl.cam.ac.uk/users/gdr11/publish.html ).
5.5: Can I buy space on an existing server?
Yes, you can. A list of sites offering WWW space for lease is
available (at the URL http://union.ncsa.uiuc.edu/www/leasing.shtml ).
5.6: How fast does my net connection need to be?
The following response to this very-frequently-asked-question was
provided by Mike Meyer (mwm@contessa.phone.net).
The answer is "It depends." What it depends on is what kind of
things you want to provide on your server. Here are some rules of
thumb to use when deciding what kind of connection you need for your
server.
The first rule of thumb is:
Don't worry about simultaneous access.
Unless you have a very large site, simultaneous access is not a
problem. If you have a very large site, you need as much bandwidth
as you can afford. There is a bit more about this below.
The second rule of thumb is:
It should take at most 5 seconds to send a page.
The five second rule dates from command line days, when that was
about how long people would wait before getting impatient with the
system. It seems like a reasonable number to use now.
Since external images/audio/etc. are somewhat exceptional, allow
more time for them. If you think they should have the same
restrictions as above, buy the bandwidth your site will need to do
so. However, the rule of thumb for external images/audio/etc is:
It should take at most 30 seconds to send an external file.
Given these rules, it's pretty straightforward to work out how large
an HTML page and external files can be. At least, it's easy after
you simplify things by ignoring IP overhead on the line, compression
on modem lines, and anything that's less than 10% of the total (or
even a little bit more than 10%).
The one simplification not to ignore is the multiple packet
round-trips it takes to get data flowing through an HTTP channel.
For modem lines, this is nearly a second for each HTTP connection,
which is significant. For leased lines, it's more like .1 or .2
seconds, which is not significant.
On a 14.4 line assumed to be sending 1.4K bytes of data/second, with
a 1 second startup, you get 4 * 1.4 or 5.6K of HTML. If you want to
include a single inline image, that's 2 seconds of startup, so
you're down to 3 * 1.4 or 4.2K of HTML + image. This means smallish
HTML pages, and simple inline images. For external files, you get 29
* 1.4 or 40K, which is still a small image. If you have a 28.8 line,
you get to double those figures; for a 9600 line, figure 2/3rds of
that size.
On a 56K leased line assumed to be sending 5K/second, you get 25K of
HTML, or mixed HTML/data. For external images, it's 150K. That
should cover any reasonable HTML document, and small to medium
external files. An MPEG movie might be a bit much.
With a T1 line assumed to be sending 150K/second, you get 750K of
HTML, or 4.5 megabytes in an external file. Barring very large
animations, this should be sufficient for anything you want to
serve. More would be faster, but it also gets drastically more
expensive.
Given the above guidelines, let's look at simultaneous access again.
Under the worst case conditions, you're using all of your line for
HTML pages, each of which takes 5 seconds to send, so your server is
sending 12 pages a minute, or 720 pages an hour, or 17,000 pages a
day (pages, not accesses; each inline image in a page generates an
access, unless the client cached it). This makes you one of the
busier sites on the web. While you'll have contention problems
before you get to this point, anything but a modem connection will
be sending most pages in a small fraction of five seconds, which
should leave plenty of bandwidth with no contention. If you have
this kind of access rates on a modem line, you should seriously
consider upgrading your connection.
The bottom line on simultaneous access is that the WWW server is
more likely to have contention with other uses of the line than with
itself. Since I don't know what else you use your line for, I can't
factor it in. You'll have to consider that issue yourself.
5.7.1: HOW DO I SET UP A CLICKABLE IMAGE MAP?
There are really two issues here: how to indicate in HTML that you
want an image to be clickable, and how to configure your server to do
something with the clicks returned by Mosaic, Chimera, and other
clients capable of delivering them.
You can read about image maps and the NCSA server at the URL
http://hoohoo.ncsa.uiuc.edu/docs/setup/admin/Imagemap.html .
Using imagemaps requires that you create a map file; you can do this
by hand or with a WYSIWYG tool.
VERY IMPORTANT: Creating imagemaps requires a real web server (not
an FTP server) and a cooperative web server administrator. It is not
usually as simple as wrapping a link around an IMG SRC tag and adding
the ISMAP directive; the server must also be told about the map file,
and the way to accomplish this varies from server to server. So read
your server documentation, and don't waste time making maps before
making sure you have the necessary tools to deliver them.
Mapedit
Mapedit (URL is:
http://sunsite.unc.edu/boutell/mapedit/mapedit.html ) is a
WYSIWYG imagemap editing tool for Microsoft Windows and the X
Window System.
MapMaker
For users of John Bradley's xv image display software for the
X Window System, Mapmaker can turn the miniature images created
by xv's Visual Schnauzer into an imagemap. This is useful if
you would like to make an entire directory of images available
(but note that you should also make textual links to allow
those with text- based browsers to download the images for
external viewing). (URL is:
http://icg.stwing.upenn.edu:80/~mengwong/mapmaker.html )
WebMap
On the Macintosh, you may want to use WebMap (URL is
ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW ). . It
produces both NCSA and CERN-compatible maps, which can also be
used with MacImagemap and a Macintosh-based server (MacImagemap
is found in the same directory). Alternatively, you may want to
use MacMapMaker, also available from
ftp://ftp.uwtc.washington.edu/pub/Mac/Network/WWW (the same
directory).
Tkmapedit
For Unix systems and other systems on which the Tk/Tcl language
toolkit has been installed, Tkmapedit provides a WYSIWYG
imagemap editor which is capable of directly testing links if
the tkWWW web browser is available. Available by anonymous FTP
from the TCL archive on ftp.aud.alcatel.com.
5.7.2: HOW DO I MAKE A "LINK" THAT DOESN'T LOAD A NEW PAGE?
Such links are useful when a form is intended to perform some action
on the server machine without sending new information to the client,
or when a user has clicked in an undefined area in an image map; these
are just two possibilities.
Rob McCool of NCSA provided the following wisdom on the subject:
Yechezkal-Shimon Gutfreund (sg04@gte.com) wrote:
: Ok, here is another bizzare request from me:
: I am currently running scripts which I "DO NOT" want to return
: any visible result. That is, not text/plain, not text/HTML, not
: image/gif. The entire results are the side effects of the
: script and nothing should be returned to the viewer.
: It would be nice to have an internally supported null viewer
: so that I could do this, more "cleanly" (ok, ok, I hear your groans).
HTTP now supports a response code of 204, which is no operation. Some
browsers such as Mosaic/X 2.* support it. To use it, make your script
a nph script and output an HTTP/1.0 204 header. Something like:
HTTP/1.0 204 No response Server: Myscript/NCSA httpd 1.1
(You can learn more about nph scripts from the NCSA server
documentation at the URL http://hoohoo.ncsa.uiuc.edu/docs .)
Essentially they are scripts that handle their own HTTP response
codes.
5.7.3: WHERE CAN I LEARN HOW TO CREATE FILL-OUT FORMS?
Writing an HTML form is easy, but the form doesn't accomplish anything
until you write a CGI program to interpret the results on the server
side! For more information, see section 5.7.14.
See the section on email forms for a simple solution to the most
commonly desired form.
5.7.3.1: How can I create hidden fields in forms (keeping state)?
Use INPUT TYPE=hidden. An example:
<INPUT TYPE=hidden NAME=state VALUE="hidden info to be returned with form">
By now, most browsers can handle the hidden type, but understand that
some browsers will fail to hide the field (and probably confuse the
user). Note that "hidden" doesn't mean "secret"; the user can always
click on "view source".
5.7.3.2: How can users send me email through their browsers?
There are two ways:
Using a mailto: URL
You can simply create a link which looks like this:
<A HREF="mailto:me@my.address">Send Me Mail</A>
This works great for browsers that support the mailto: URL.
Perhaps 80% of web users will be able to use such a link. But
not all browsers support it.
Installing an email form
If you have access to the server's configuration files, or if
your server administrator permits users to create their own CGI
scripts, you can create a form which sends mail to you from any
browser that supports forms. I've written a simple email forms
package (URL is: http://siva.cshl.org/email/index.html ), which
does it in ANSI C. There is also a package written in Perl,
known as the WWW Mailto Gateway (URL is
http://www.mps.ohio-state.edu/mailto/mailto_info.html ).
GetComments (URL is:
http://everest.cs.ucdavis.edu/~hoagland/getcomments.html) is a
more general package, also written in Perl, which can handle
many different types of comment forms.
If you want to learn how these forms actually work, see section
5.7.14.
5.7.4: HOW DO I COMMENT AN HTML DOCUMENT?
Use the <!-- tag at the beginning of EACH line commented out; close
this for EACH line with the --> tag. Note that comments do not nest,
and the sequence "--" may not appear inside a comment except as part
of the closing --> tag. (It's officially allowed, but some browsers
won't handle it properly.)
You should not try to use this to "comment out" HTML that would
otherwise be shown to the user, since some browsers (notably Mosaic)
will still pay attention to tags inside the comment and close it
prematurely.
Thanks to Joe English for clearing up this issue.
5.7.5: HOW CAN I CREATE DECENT-LOOKING TABLES AND STOP USING <PRE>...
</PRE>?
Tables are a standard feature in HTML Level 3, a new version of HTML.
Unfortunately, they are at present implemented only by the latest NCSA
Mosaic versions and the Viola and Emacs-W3 browsers, to my knowledge.
In addition, most implementations are incomplete. In some
implementations, at the time of this writing, text in tables cannot be
selected and/or cannot be a link.
However, there is a way to use HTML Level 3 tables now and convert
them automatically to HTML, allowing you to design proper tables and
install those pages directly when table support arrives in the
majority of clients. You can do this using the html+tables package, by
Brooks Cutter (bcutter@paradyne.com), which is available for anonymous
ftp from sunsite.unc.edu in the directory
pub/packages/infosystems/WWW/tools/html+tables.shar. This package
requires the shell language Perl, which is primarily used on Unix
systems but is also available for other systems (such as MSDOS
machines). html+tables accepts HTML Level 3 and outputs html using the
<PRE>...</PRE> construct to represent tables, allowing you to write
HTML Level 3 now, knowing that it will look better when clients are
ready for it.
5.7.6: WHAT IS HTML LEVEL 3 AND WHERE CAN I LEARN MORE ABOUT IT?
HTML Level 3, also known as HTML+, is an enhanced version of HTML
designed to address some of the limitations of HTML. HTML Level 3
supports true tables, right-justified text, centered text, line breaks
that do not double space, and many other desired features.
However, most clients support only a handful of HTML Level 3 features
(such as the partial implementation of tables in Mosaic) at the time
of this writing. If you have access to a Unix system with the X Window
System installed, you can try out many features of HTML Level 3 using
the experimental Arena browser.
You can access information about new developments in HTML at the CERN
server (at the URL
http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html ).
(HTML Level 1 is the original version. HTML Level 2 is essentially the
same, but with the addition of forms.)
5.7.7: HOW CAN I MAKE TRANSPARENT AND INTERLACED GIFS? AND WHAT ARE THEY?
Transparent GIFs are useful because they appear to blend in smoothly
with the user's display, even if the user has set a background color
that differs from that the developer expected. They do this by
assigning one color to be transparent -- if the web browser supports
transparency, that color will be replaced by the browser's background
color, whatever it may be.
Interlaced GIFs appear first with poor resolution and then improve in
resolution until the entire image has arrived, as opposed to arriving
linearly from the top row to the bottom row. This is great to get a
quick idea of what the entire image will look like while waiting for
the rest. This doesn't do much for you if your web browser doesn't
support progressive display as the image is downloaded, but
non-progressive-display web browsers will still display interlaced
GIFs once they have arrived in their entirety.
To create transparent and interlaced GIFs, check out David Koblas'
giftool, a program which can manipulate those options and many more
aspects of your GIF file.
In addition, there is a document explaining transparent GIFs available
at the URL http://melmac.corp.harris.com/transparent_images.html . You
can fetch the program giftrans by anonymous ftp from
ftp.rz.uni-karlsruhe.de at the path /pub/net/www/tools/giftrans.c.
There is also a Perl Script (URL is:
http://www.omron.co.jp:80/~jfriedl/perl/ ) which makes transparent
GIFs.
There is also a utility for the Macintosh, Transparency (URL is:
http://www.med.cornell.edu/~giles/projects.html#transparency).
5.7.8: HOW COME MAILTO: URLS DON'T WORK?
The mailto: URL is a feature found in Lynx, Netscape, Spry Mosaic, the
latest NCSA Mosaics, Emacs w3 mode and many other browsers. In
general, about 80% of web browsers support mailto: at the time of this
writing. However, it is not in numerous older browsers. In the
meantime, you can set up forms which send mail to you; see Section
5.7.3.2.
5.7.9: HOW CAN I RESTRICT AND CONTROL ACCESS TO MY SERVER?
All major servers have features that allow you to limit access to
particular sites, and many clients have authentication features that
allow you to identify specific users. There is a tutorial on security
and user authentication with the NCSA server and Mosaic available,
written by Marc Andreessen (URL is
http://wintermute.ncsa.uiuc.edu:8080/auth-tutorial/tutorial.html ).
See your server documentation for further information.
5.7.10: WHICH FORMAT IS BETTER FOR WWW IMAGE PURPOSES, JPEG OR GIF?
JPEG does a better job with realistic images such as scanned
photographs. Most browsers cannot handle inline JPEGs, however, so you
must link to them as external images (using a regular <A HREF...>
instead of <IMG SRC...>).
GIF does a better job with crisp, sharp images, such as those
typically used to construct buttons, graphs and the like. All browsers
that can display graphics at all can display GIFs inline.
5.7.11: HOW CAN I MIRROR PART OF ANOTHER SERVER?
Scripts are available to do this, but at this time they are not very
friendly to the server you are attempting to mirror; their behavior
resembles that of the more poorly written WWW robots. If you are
trying to improve access times to a distant server, you will likely
find the "proxy" capabilities of CERN's WWW server to be a more
effective and general solution to your problem.
5.7.12: HOW CAN I KEEP ROBOTS OFF MY SERVER?
Programs that automatically traverse the web can be quite useful, but
have the potential to make a serious mess of things. Every so often
someone will write a "depth-first" searching robot that brings servers
to their knees. See the section on writing robots (4.10) for details.
Fortunately, most robots on the web follow a simple protocol by which
you can keep them off your server if you wish, or keep them out of
portions of your server which are robot traps (ie, they contain an
infinite number of possible links). Read the document World Wide Web
Robots, Wanderers and Spiders (URL is:
http://web.nexor.co.uk/mak/doc/robots/robots.html ) and learn about
the emerging standards for exclusion of robots from areas in which
they are not wanted. You can also read about existing robots there,
including useful cataloging robots you probably do not want to keep
off your server.
5.7.13: HOW CAN I KEEP STATISTICS ABOUT MY WEB SERVER?
There are several tools which can generate statistics about your web
server:
getstats
getstats is a versatile log analyzer, also written in C, which
provides reports for various time periods with a high degree of
flexibility. Add-on packages have been written to generate
reports in HTML and also to generate graphs. You can access the
getstats home page for more information (URL is
http://www.eit.com/software/getstats/getstats.html ), or obtain
the package by anonymous FTP from ftp.eit.com in the directory
/pub/web.software/getstats.
WebStat
WebStat is a package written in the language Python which
supplies statistics on usage by domain, country, etc., with
daily, weekly, monthly and annual reports available. You will
need Python in order to use it. See the WebStat home page (URL
is
http://www.pegasus.esprit.ec.org/people/sijben/statistics/advertisment.html
) for details, or obtain Python from ftp.cwi.nl in
the directory /pub/python and WebStat from
ftp.pegasus.esprit.ec.org in the directory /pub/misc.
Wusage
Wusage, which I wrote, is a C program which generates simple
weekly reports in HTML, with inline image graphs displaying
server growth and the distribution of accesses by continent.
You can also exclude irrelevant accesses (inline images, local
machines, etc.) from the results. Read the Wusage home page
(URL is http://siva.cshl.org/wusage.html ) for more
information, or obtain Wusage by anonymous FTP from
isis.cshl.org in the directory pub/wusage.
wwwstat
wwwstat is a full-featured log analyzer written in the language
Perl. (See the newsgroup comp.lang.perl for more information
about the language.) See the wwwstat home page (URL is
http://www.ics.uci.edu/WebSoft/wwwstat/ ) for more information,
or obtain the package by anonymous FTP from liege.ics.uci.edu
in the directory /pub/arcadia/wwwstat. See also gwstat (URL is
http://dis.cs.umass.edu/stats/gwstat.html ), a package which
produces GIF graphs from the output of wwwstat.
5.7.14: I WANT TO GENERATE WEB PAGES FROM A PROGRAM. DO I HAVE TO WRITE A
CUSTOM SERVER?
No, you will not need to write a custom server. Most web servers
support one variation or another of a standard for adding your own
programs to the web server. The standard is called CGI (Common Gateway
Interface).
Marc Hedlund has written a FAQ on CGI programming (URL is:
http://www.halcyon.com/hedlund/cgi-faq/ ) which makes a good
introduction to the subject. The standard itself can be found at NCSA
(URL is: http://hoohoo.ncsa.uiuc.edu/ ).
5.7.14.1: How can I generate GIFs on the fly from my CGI scripts?
If you want to generate GIF images on the fly as part of your
application, examine the gd library (URL is:
http://siva.cshl.org/gd/gd.html ). Hint: your HTML page and your
inline images are separate documents with separate URLs. Generate them
in response to separate requests! (Yes, there are tricks to speed this
up, but be careful not to break inline images on HTML pages you didn't
write that refer to your gd-generated image.)
It's also possible to use gnuplot and the pbmplus utilities. This is
slower, but can require less programming if gnuplot is sufficient for
your purposes. (See archie for both tools.)
6: WHERE CAN I DISCUSS THE WORLD WIDE WEB?
6.1: What newsgroups discuss the Web?
You can find discussion of World Wide Web topics in three newsgroups,
and one newsgroup which will soon be removed:
comp.infosystems.www.users
A forum for the discussion of WWW client software and its use
in contacting various Internet information sources. New user
questions, client setup questions, client bug reports,
resource-discovery questions on how to locate information on
the web that can't be found by the means detailed in the FAQ
and comparison between various client packages are among the
acceptable topics for this group. Please specify what browser
and what system type (Windows, Mac, Unix, etc.) your post is
about if you are asking questions about a specific program.
comp.infosystems.www.providers
A forum for the discussion of WWW server software and the use
of said software to present information to users. General
server design, setup questions, server bug reports, security
issues, HTML page design and other concerns of information
providers are among the likely topics for this group.
comp.infosystems.www.misc
A forum for general discussion of WWW (World Wide Web)- related
topics that are NOT covered by the other newsgroups in the
hierarchy. This will likely include discussions of the Web's
future, politicking regarding changes in the structure and
protocols of the web that affect both clients and servers, et
cetera.
comp.infosystems.www.announce
A moderated forum for the announcement of new and updated World
Wide Web resources and software.
comp.infosystems.www (DEFUNCT)
The old catch-all newsgroup, which may still exist on your
system but was officially removed on September 7th, 1994,
according to David Lawrence, moderator of
news.announce.newgroups. If your system still carries this
group, ask your administrator to remove it.
6.2: What mailing lists discuss the Web?
www-talk@info.cern.ch
Address: www-talk@info.cern.ch for CONTRIBUTIONS ONLY.
Administration: listserv@info.cern.ch (robot)
www-talk-request@info.cern.ch (human). Description: Technical
discussion, W3 related. Experts to experts. General questions
to the newsgroups, please. Archive: Not currently served, but
kept.
www-announce@info.cern.ch
Address: www-announce@info.cern.ch. NOT FOR GENERAL USE -
serious low-volume announcements only. Administration:
listserv@info.cern.ch (robot),
www-announce-request@info.cern.ch (human). Description: Low
volume summary announcemements of product releases, etc.
Archive: Not currently public.
7: I WANT TO KNOW MORE
To find out more, use the web. This FAQ hopefully provides enough
information for you to locate and install a browser on your system. If
you have system specific questions regarding FTP, networking and the
like, please consult newsgroups relevant to your particular hardware
and operating system!
Once you're up and running, you may wish to consult the World Wide Web
Primer by Nathan Torkington. It is available at the URL
http://www.vuw.ac.nz/who/Nathan.Torkington/ideas/www-primer.html .
Later you may return to this FAQ for answers to some of the more
advanced questions. I encourage you to check out the changes listed
early in the document each time the FAQ appears.
8: CREDITS
Maintainer (11/93 to present): Thomas Boutell, boutell@netcom.com
Former Maintainer (until 11/93): Nathan Torkington,
Nathan.Torkington@vuw.ac.nz
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