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<h3>Apache HTTP Server Version 1.3</h3>
<p><small><em>Is this the version you want? For more recent
versions, check our <a href="/docs/">documentation
index</a>.</em></small></p>
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<h1 align="CENTER">Overview of new features</h1>
<h2>New Features with Apache 1.0</h2>
<p>New features with this release, as extensions of the Apache
functionality (see also more detailed <code>CHANGES</code>
file) in the source directory. Because the core code has
changed so significantly, there are certain liberties that
earlier versions of Apache (and the NCSA daemon) took that
Apache 1.0 is pickier about - please check the <a
href="misc/compat_notes.html">compatibility notes</a> if you
have any problems.</p>
<ul>
<li>
API for server extensions --- see below for a brief sermon
on philosophy, or see <a
href="misc/API.html">src/API.html</a> for an actual
overview. Most server functionality (including includes,
CGI, and most forms of access control) are actually
implemented as API-conformant modules; you can also do
other neat stuff (we've included a sample module, for
instance, which one of us is using to track click-trails
using the <a
href="http://home.netscape.com/newsref/std/cookie_spec.html">
Netscape cookie mechanism</a>, for visitors who come in
through Netscape clients). <a
href="mod/mod_dld.html">Modules</a> can also be loaded
dynamically using GNU DLD.
<p>The API is not yet quite stable (see src/TODO for some
possible changes), but anything done now will be easily
adapted for future versions --- after all, we have more
modules to adapt than you do.</p>
</li>
<li><a href="process-model.html">New Process Model - much
less forking, no fixed number of children.</a> We found that
many people were using values for "MaxServers" either too
high or too low, and were hanging themselves on it. The model
we adopted is still based on long-lived minimal-forking
processes, but instead of specifying one number of persistent
processes, the web-master specifies a maximum and minimum
number of processes to be "spare" - every couple of seconds
the parent checks the actual number of spare servers and
adjusts accordingly. This should keep the number of servers
concurrently running relatively low while still ensuring
minimal forking.</li>
<li><a href="vhosts/"><VirtualHost> (the configuration
directive for multiple-homed servers)</a> is more general
now. Just about any srm.conf or httpd.conf command can go in
a <Virtualhost> section, with the following specific
exceptions: ServerType, UserId, GroupId, StartServers,
MaxRequestsPerChild, BindAddress, PidFile, TypesConfig,
ServerRoot.</li>
<li><a href="content-negotiation.html">Support for content
negotiation of languages through MultiViews</a> (*.fr, *.de,
*.en suffixes), via the new AddLanguage and LanguagePriority
commands (code written by Florent Guillaume,
guillaum@clipper.ens.fr).</li>
<li>Significant internal cleanups and rearrangements. The two
externally visible consequences of this are that just about
all of the unchecked fixed limits are gone, and that the
server is somewhat pickier about config file syntax (noting
and complaining about extraneous command arguments or other
stuff at the end of command lines).</li>
<li>XBITHACK is a run-time option, and can be selectively
enabled per directory --- the -DXBITHACK compile-time option
just changes the default. The command which configures it is
"XBitHack", which is allowed everywhere "Options" is; this
takes an argument --- "XBitHack Off" turns it off; "XBitHack
On" gets you the NCSA -DXBITHACK behavior; and "XBitHack
Full" gets you the Apache GXBIT stuff on top of that.
(-DXBITHACK makes "Full" the default; otherwise, it defaults
"Off").</li>
<li>TransferLog can specify a program which gets the log
entries piped to it, a la 'TransferLog "|
/var/www/my-perl-script -arg valu"' --- this should give the
same SIGTERM/pause/SIGKILL treatment to the logging process
on server restarts that a CGI script gets on an aborted
request. NB the server is counting on the logging process to
work, and will probably hang or worse if it dies.</li>
<li><a href="mod/mod_log_config.html">Configurable logging
module</a> --- this is a replacement for the standard
plane-jane Common Log Format code, which supports a LogFormat
directive which allows you to control the formatting of
entries in the TransferLog, and add some new items if you
like (in particular, Referer and User-Agent).
EXPERIMENTAL.</li>
</ul>
<hr />
<h2>Other features of Apache</h2>
<ul>
<li><a href="mod/mod_dld.html">Dynamically loading modules
using GNU DLD</a></li>
<li><a href="mod/mod_imap.html">Imagemap Module</a></li>
<li><a href="mod/mod_dir.html#directoryindex">Multiple
DirectoryIndex filenames</a></li>
<li><a href="mod/mod_asis.html">"Send as is" file
types</a></li>
<li><a href="mod/mod_include.html#xbithack">XBITHACK last
modified</a></li>
</ul>
<hr />
<h3 align="CENTER">Apache HTTP Server</h3>
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