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  Apache HTTP Server Version 1.3
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<H1 ALIGN="CENTER">Overview of New Features in Apache 1.3</H1>

<P>New features with this release, as extensions of the Apache
functionality. Because the core code has changed so
significantly, there are certain liberties that earlier versions of
Apache (and the NCSA daemon) took that recent Apache versions are
pickier about - please check the
<A HREF="misc/compat_notes.html">compatibility notes</A> if you have any
problems.</P>

<P>If you're upgrading from Apache 1.2, you may wish to read
the <A HREF="upgrading_to_1_3.html">upgrade notes</A>.

<P>Enhancements: <A HREF="#core">Core</A> |
<A HREF="#performance">Performance</A> |
<A HREF="#config">Configuration</A> |
<A HREF="#mod">Modules</A> |
<A HREF="#api">API</A> |
<A HREF="#misc">Misc</A>

<P><HR>

<H2><A NAME="core">Core Enhancements:</A></H2>

<DL>
<DT><STRONG><A HREF="dso.html">Dynamic Shared Object (DSO) support</A></STRONG>
<DD>Apache modules may now be loaded at runtime; this means that
    modules can be loaded into the server process space only when necessary,
    thus overall memory usage by Apache will be significantly reduced.  DSO
    currently is supported on FreeBSD, OpenBSD, NetBSD, Linux, Solaris, SunOS,
    Digital UNIX, IRIX, HP/UX, UnixWare, AIX, ReliantUnix and generic SVR4
    platforms.

<DT><STRONG><A HREF="windows.html">Support for Windows NT/95</A></STRONG>
<DD>Apache now experimentally supports the Windows NT and Windows 95
    operating systems.

<DT><STRONG><A HREF="sourcereorg.html">Re-organized 
    Sources</A></STRONG>
<DD>The source files for Apache have been re-organized. The main
    difference for Apache users is that the "Module" lines in
    <CODE>Configuration</CODE> have been replaced with "AddModule"
    with a slightly different syntax.  For module authors there are
    some changes designed to make it easier for users to add their
    module.

<DT><STRONG>Reliable Piped Logs</STRONG>
<DD>On almost all Unix architectures Apache now implements "reliable"
    piped logs in <A
    HREF="mod/mod_log_config.html">mod_log_config</A>.  Where reliable
    means that if the logging child dies for whatever reason, Apache
    will recover and respawn it without having to restart the entire
    server.  Furthermore if the logging child becomes "stuck" and
    isn't reading its pipe frequently enough Apache will also restart
    it.  This opens up more opportunities for log rotation, hit
    filtering, real-time splitting of multiple vhosts into separate
    logs, and asynchronous DNS resolving on the fly.
</DL>

<P><HR>

<H2><A NAME="performance">Performance Improvements</A></H2>

<UL>
 <LI>IP-based virtual hosts are looked up via hash table.
 <LI>&lt;Directory&gt; parsing speedups.
 <LI>The critical path for static requests has fewer system calls.
     This generally helps all requests.  (45 syscalls for a static
     request in 1.2 versus 22 in 1.3 in a well tuned
     configuration).
 <LI><A HREF="mod/mod_proxy.html#proxyreceivebuffersize">
     <CODE>ProxyReceiveBufferSize</CODE></A> directive gives
     <CODE>mod_proxy</CODE>'s outgoing connections larger network
     buffers, for increased throughput.
 <LI>The low level I/O routines use <CODE>writev</CODE> (where
     available) to issue multiple writes with a single system call.
     They also avoid copying memory into buffers as much as
     possible.  The result is less CPU time spent on transferring
     large files.
 <LI>Static requests are served using <CODE>mmap</CODE>, which
     means bytes are only copied from the disk buffer to the
     network buffer directly by the kernel.  The program never
     copies bytes around, which reduces CPU time.  (Only where
     available/tested.)
 <LI>When presented with a load spike, the server quickly adapts by
     spawning children at faster rates.
 <LI>The code which dispatches modules was optimized to avoid
     repeatedly skipping over modules that don't implement certain
     phases of the API.  (This skipping showed up as 5% of the cpu
     time on profiles of a server with the default module mix.)
 <LI>Revamp of the Unix scoreboard management code so that less
     time is spent counting children in various states.  Previously
     a scan was performed for each hit, now it is performed only
     once per second.  This should be noticeable on servers running
     with hundreds of children and high loads.
 <LI>New serialization choices improve performance on Linux, and
     IRIX.
 <LI><CODE><A
     HREF="mod/mod_log_config.html">mod_log_config</A></CODE> can
     be compile-time configured to buffer writes.
 <LI>Replaced <CODE>strncpy()</CODE> with
     <CODE>ap_cpystrn()</CODE>, a routine which doesn't have to
     zero-fill the entire result.  This has dramatic effects on
     <CODE>mod_include</CODE> speed.
 <LI>Additions to the internal "table" API (used for keeping lists
     of key/value string pairs) provide for up to 20% performance
     improvement in many situations.
</UL>

<P>See <A HREF="misc/perf-tuning.html">the new performance
documentation</A> for more information.

<P><HR>

<H2><A NAME="config">Configuration Enhancements</A></H2>

<DL>
<DT><STRONG>Unified Server Configuration Files</STRONG></DT>
<DD><EM>(Apache 1.3.4)</EM> The contents of the three
    server configuration files (<SAMP>httpd.conf</SAMP>,
    <SAMP>srm.conf</SAMP>, and <SAMP>access.conf</SAMP>) have
    been merged into a single <SAMP>httpd.conf</SAMP> file.
    The <SAMP>srm.conf</SAMP> and <SAMP>access.conf</SAMP> files
    are now empty except for comments directing the Webmaster
    to look in <SAMP>httpd.conf</SAMP>.  In addition, the
    merged <SAMP>httpd.conf</SAMP> file has been restructured
    to allow directives to appear in a hopefully more
    intuitive and meaningful order.
</DD>
<DT><STRONG>Continuation Lines in config files</STRONG></DT>
<DD>Directive lines in the server configuration files may now be
    split onto multiple lines by using the canonical Unix continuation
    mechanism, namely a '\' as the last non-blank character on the
    line to indicate that the next line should be concatenated.
</DD>
<DT><STRONG>Apache Autoconf-style Interface (APACI)</STRONG>
<DD>Until Apache 1.3 there was no real out-of-the-box batch-capable
    build and installation procedure for the complete Apache
    package. This is now provided by a top-level
    <CODE>configure</CODE> script and a corresponding top-level
    <CODE>Makefile.tmpl</CODE> file. The goal is to provide a GNU
    Autoconf-style frontend which is capable to both drive the old
    <CODE>src/Configure</CODE> stuff in batch and additionally
    installs the package with a GNU-conforming directory layout.  Any
    options from the old configuration scheme are available plus a lot
    of new options for flexibly customizing Apache.<BR>
    <STRONG>Note:</STRONG> The default installation layout has changed
    for Apache 1.3.4.  See the files <CODE>README.configure</CODE> and
    <CODE>INSTALL</CODE> for more information.

<DT><STRONG>APache eXtenSion (APXS) support tool</STRONG>
<DD>Now that Apache provides full support for loading modules under
    runtime from dynamic shared object (DSO) files, a new support tool
    <CODE>apxs</CODE> was created which provides off-source building,
    installing and activating of those DSO-based modules. It
    completely hides the platform-dependent DSO-build commands from
    the user and provides an easy way to build modules outside the
    Apache source tree. To achieve this APACI installs the Apache C
    header files together with the <CODE>apxs</CODE> tool.
 
<DT><A HREF="install.html#install"><STRONG>Default Apache directory 
    path changed to <CODE>/usr/local/apache/</CODE></STRONG></A><BR>
<DD>The default directory for the apache ServerRoot changed from the
    NCSA-compatible <CODE>/usr/local/etc/httpd/</CODE> to
    <CODE>/usr/local/apache/</CODE>.  This change covers only the
    default setting (and the documentation); it is of course possible
    to override it using the <A HREF="invoking.html"> -d
    <EM>ServerRoot</EM> and -f <EM>httpd.conf</EM></A> switches when
    starting apache.

<DT><STRONG>Improved HTTP/1.1-style Virtual Hosts</STRONG>
<DD>The new <A
    HREF="mod/core.html#namevirtualhost"><CODE>NameVirtualHost</CODE></A>
    directive is used to list IP address:port pairs on which
    HTTP/1.1-style virtual hosting occurs.  This is vhosting based on
    the <CODE>Host:</CODE> header from the client.  Previously this
    address was implicitly the same as the "main address" of the
    machine, and this caused no end of problems for users, and was not
    powerful enough.  Please see the <A
    HREF="vhosts/index.html">Apache Virtual Host documentation</A> for
    further details on configuration.

<DT><STRONG><CODE>Include</CODE> directive</STRONG>
<DD>The <A HREF="mod/core.html#include" ><CODE>Include</CODE></A>
    directive includes other config files immediately at that point in
    parsing.

<DT><STRONG>-S command line option for debugging vhost setup</STRONG>
<DD>If Apache is invoked with the <CODE>-S</CODE> command line option
    it will dump out information regarding how it parsed the
    <CODE>VirtualHost</CODE> sections.  This is useful for folks
    trying to debug their virtual host configuration.

<DT><STRONG>Control of HTTP methods</STRONG>
<DD><A HREF="mod/core.html#limitexcept">&lt;LimitExcept&gt; and
    &lt;/LimitExcept&gt;</A> are used to enclose a group of access control
    directives which will then apply to any HTTP access method not listed in
    the arguments; i.e., it is the opposite of a <Limit> section and can be
    used to control both standard and nonstandard/unrecognized methods.
</DL>

<P><HR>

<H3><A NAME="mod">Module Enhancements</A></H3>

<DL>
<DT><A HREF="mod/mod_negotiation.html"><STRONG>Improved mod_negotiation
    </STRONG></A><BR>
<DD>The optional content negotiation (MultiViews) module has been completely
    overhauled for Apache 1.3.4, incorporating the latest HTTP/1.1
    revisions and the experimental Transparent Content Negotion features
    of RFC 2295 and RFC 2296.

<DT><A HREF="mod/mod_speling.html"><STRONG>NEW - Spelling correction 
    module</STRONG></A><BR>
<DD>This optional module corrects frequently occurring spelling and
    capitalization errors in document names requested from the server.

<DT><A HREF="mod/mod_setenvif.html"><STRONG>NEW - Conditional setting of 
    environment variables</STRONG></A><BR>
<DD>The addition of
    <A HREF="mod/mod_setenvif.html#SetEnvIf">
    <CODE>SetEnvIf</CODE></A> and
    <A HREF="mod/mod_setenvif.html#SetEnvIfNoCase">
    <CODE>SetEnvIfNoCase</CODE></A>.  These allow you to set
    environment variables for server and CGI use based upon attributes
    of the request.

<DT><STRONG><A HREF="mod/mod_mime_magic.html">NEW - "Magic"
MIME-typing</A></STRONG>
<DD>The optional <CODE>mod_mime_magic</CODE> has been
    added. It uses "magic numbers" and other hints from a file's
    contents to figure out what the contents are. It then uses this
    information to set the file's media type, if it cannot be
    determined by the file's extension.

<DT><STRONG><A HREF="mod/mod_unique_id.html">NEW - Unique Request 
    Identifiers</A></STRONG>
<DD><A HREF="mod/mod_unique_id.html">mod_unique_id</A> can be included
    to generate a unique identifier that distinguishes a hit from
    every other hit.  ("Unique" has some restrictions on it.)  The
    identifier is available in the environment variable
    <CODE>UNIQUE_ID</CODE>.

<DT><STRONG>mod_proxy enhancements:</STRONG>
<UL>
<LI>Easier and safer authentification for ftp proxy logins:
    When no ftp user name and/or password is specified in the
    URL, but the destination ftp server requires one, apache now
    returns a "[401] Authorization Required" status. This status code
    usually makes the client browser pop up an "Enter user name and
    password" dialog, and the request is retried with the given user
    authentification. That is slightly more secure than specifying
    the authentication information as part of the request URL,
    where it could be logged in plaintext by older proxy servers.
<LI>The new <SAMP>AllowCONNECT</SAMP> directive allows configuration
    of the port numbers to which the proxy CONNECT method may connect.
    That allows proxying to https://some.server:8443/ which resulted
    in an error message prior to Apache version 1.3.2.
<LI>The proxy now supports the HTTP/1.1 "Via:" header as specified in
    RFC2068. The new
    <A HREF="mod/mod_proxy.html#proxyvia"><CODE>ProxyVia</CODE></A>
    directive allows switching "Via:" support off or on, or
    suppressing outgoing "Via:" header lines altogether for privacy
    reasons.
<LI>The "Max-Forwards:" TRACE header specified in HTTP/1.1 is now
    supported. With it, you can trace the path of a request along a
    chain of proxies (if they, too, support it).
<LI><A
    HREF="mod/mod_proxy.html#noproxy"><CODE>NoProxy</CODE></A> and <A
    HREF="mod/mod_proxy.html#proxydomain"><CODE>ProxyDomain</CODE></A>
    directives added to proxy, useful for intranets.
<LI>New <CODE><A HREF="mod/mod_proxy.html#proxypassreverse">
    ProxyPassReverse</A></CODE> directive.  It lets Apache adjust the
    URL in the <TT>Location</TT> header on HTTP redirect
    responses. 
<LI>Easier navigation in ftp server directory trees.
</UL>

<DT><A HREF="mod/mod_include.html#flowctrl"><STRONG>Enhanced 
    <CODE>mod_include</CODE> string comparisons</STRONG></A><BR>
<DD>The string-based server-side include (SSI) flow-control directives
    now include comparison for less-than (&lt;), less-than-or-equal
    (&lt;=), greater-than (&gt;), and greater-than-or-equal (&gt;=).
    Previously comparisons could only be made for equality or
    inequality.

<DT><STRONG>ServerRoot relative auth filenames</STRONG>
<DD>Auth filenames for the various authentication modules are now
    treated as relative to the ServerRoot if they are not full paths.

<DT><A HREF="mod/mod_autoindex.html"><STRONG>Enhancements to directory
    indexing:</STRONG></A>

<DD><UL>
    <LI><STRONG>Code split:</STRONG>The <CODE>mod_dir</CODE> module has
        been split in two, with <A
        HREF="mod/mod_dir.html">mod_dir</A> handling directory index
        files, and <A HREF="mod/mod_autoindex.html">mod_autoindex</A>
        creating directory listings.  Thus allowing folks to remove the
        indexing function from critical servers.

    <LI><STRONG>Sortable:</STRONG> Clicking on a column title will now sort 
        the  listing in order by the values in that column.  This feature can
        be disabled using the <CODE>SuppressColumnSorting</CODE> <A
        HREF="mod/mod_autoindex.html#indexoptions">IndexOptions</A>
        keyword.

    <LI><A HREF="mod/mod_autoindex.html#indexoptions:suppresshtmlpreamble">
        <CODE><STRONG>SuppressHTMLPreamble</STRONG></CODE></A> can be used if
        your README.html file includes its own HTML header.

    <LI>The <A HREF="mod/mod_autoindex.html#indexoptions">
        <CODE><STRONG>IndexOptions</STRONG></CODE></A> directive now allows
        the use of incremental prefixes (+/- to add/remove the respective
        keyword feature, as was already possible for the
        <A HREF="mod/core.html#options">Options</A> directive) to its
        keyword arguments. Multiple IndexOptions directives applying
        to the same directory will now be merged.

    <LI><A HREF="mod/mod_autoindex.html#indexoptions:iconheight"
        ><STRONG><CODE>IconHeight</CODE></STRONG></A> and
	<A HREF="mod/mod_autoindex.html#indexoptions:iconwidth"
        ><STRONG><CODE>IconWidth</CODE></STRONG></A>
        let you set height and width attributes to the
        <CODE>&lt;IMG&gt;</CODE> tag in directory listings.

    <LI>The new <A HREF="mod/mod_autoindex.html#indexoptions:namewidth"
        ><STRONG><CODE>NameWidth</CODE></STRONG></A> keyword to the
        <A HREF="mod/mod_autoindex.html#indexoptions">IndexOptions</A>
	directive lets you set the number of columns for
	<A HREF="mod/mod_autoindex.html#indexoptions:fancyindexing">"fancy"
	directory listings</A>. If set to an '*' asterisk, the name width
	will be adjusted automatically.

    <LI>The <A HREF="mod/mod_autoindex.html#fancyindexing"
        ><SAMP>FancyIndexing</SAMP></A> directive now correctly has
        the same impact as 
        <A HREF="mod/mod_autoindex.html#indexoptions:fancyindexing"><SAMP>IndexOptions&nbsp;FancyIndexing</SAMP></A>
	without replacing the effect of any existing <SAMP>IndexOptions</SAMP>
	directive.

    </UL>

<DT><STRONG>Less Buffering of CGI Script Output</STRONG>
<DD>In previous versions of Apache, the output from CGI scripts would
    be internally buffered by the server, and wouldn't be forwarded to
    the client until either the buffers were full or the CGI script
    completed.  As of Apache 1.3, the buffer to the client is flushed
    any time it contains something and the server is waiting for more
    information from the script.  This allows CGI script to provide
    partial status reports during long processing operations.


<DT><STRONG><A HREF="mod/mod_alias.html">Regular Expression support for
    <CODE>Alias</CODE> and <CODE>Redirect</CODE></A></STRONG>
<DD>New <A HREF="mod/mod_alias.html#aliasmatch"><CODE>AliasMatch</CODE></A>,
    <A HREF="mod/mod_alias.html#scriptaliasmatch"
    ><CODE>ScriptAliasMatch</CODE></A>, and
    <A HREF="mod/mod_alias.html#redirectmatch"><CODE>RedirectMatch</CODE></A>
    directives allow for the use of regular expression matching.
    Additionally, new
    <A HREF="mod/core.html#directorymatch"
    ><CODE>&lt;DirectoryMatch&gt;</CODE></A>,
    <A HREF="mod/core.html#locationmatch"
    ><CODE>&lt;LocationMatch&gt;</CODE></A>,
    and
    <A HREF="mod/core.html#filesmatch"><CODE>&lt;FilesMatch&gt;</CODE></A>
    sections provide a new syntax for regular expression sectioning.

<DT><STRONG><A
    HREF="mod/mod_info.html#addmoduleinfo"><CODE>AddModuleInfo</CODE></A>
    directive added to <A
    HREF="mod/mod_info.html">mod_info</A></STRONG>
<DD>Allows additional information to be listed along with a specified
    module.

<DT><STRONG>Absence of any <CODE>TransferLog</CODE> disables 
    logging</STRONG>
<DD>If no <A HREF="mod/mod_log_config.html#transferlog"
    ><CODE>TransferLog</CODE></A> directive is given then no log is
    written.  This supports co-existence with other logging modules.

<DT><STRONG>Ability to name logging formats</STRONG>
<DD>The <A
    HREF="mod/mod_log_config.html#logformat"><CODE>LogFormat</CODE></A>
    directive has been enhanced to allow you to give nicknames to
    specific logging formats.  You can then use these nicknames in
    other <CODE>LogFormat</CODE> and <A
    HREF="mod/mod_log_config.html#customlog"
    ><CODE>CustomLog</CODE></A> directives, rather than having to
    spell out the complete log format string each time.

<DT><STRONG>Conditional logging</STRONG>
<DD><A HREF="mod/mod_log_config.html#customlog-conditional">mod_log_config</A>
    now supports logging based upon environment variables.
    mod_log_referer and mod_log_agent are now deprecated.

<DT><STRONG>mod_cern_meta configurable per-directory</STRONG>
<DD><A HREF="mod/mod_cern_meta.html">mod_cern_meta</A> is now
    configurable on a per-directory basis.

<DT><STRONG>New map types for
    <A HREF="mod/mod_rewrite.html#RewriteMap"><CODE>RewriteMap</CODE></A>
    directive</STRONG>
<DD>The new map types `Randomized Plain Text' and `Internal Function'
    were added to the <CODE>RewriteMap</CODE> directive of
    mod_rewrite.  They provide two new features: First, you now can
    randomly choose a sub-value from a value which was looked-up in a
    rewriting map (which is useful when choosing between backend
    servers in a Reverse Proxy situation). Second, you now can
    translate URL parts to fixed (upper or lower) case (which is
    useful when doing mass virtual hosting by the help of
    mod_rewrite).

<DT><STRONG>CIDR and Netmask access control</STRONG>
<DD><A HREF="mod/mod_access.html">mod_access</A> directives now
    support CIDR (Classless Inter-Domain Routing) style prefixes, and
    netmasks for greater control over IP access lists.

</DL>
<P><HR>

<H3><A NAME="api">API Additions and Changes</A></H3>

<P>For all those module writers and code hackers:

<DL>
<DT><STRONG><CODE>child_init</CODE></STRONG>
<DD>A new phase for Apache's API is called once per "heavy-weight process,"
    before any requests are handled. This allows the module to set up
    anything that need to be done once per processes. For example,
    connections to databases.

<DT><STRONG><CODE>child_exit</CODE></STRONG>
<DD>A new phase called once per "heavy-weight process," when it is
    terminating.  Note that it can't be called in some fatal cases (such
    as segfaults and kill -9).  The <CODE>child_init</CODE> and
    <CODE>child_exit</CODE> functions are passed a pool whose lifetime is
    the same as the lifetime of the child (modulo completely fatal
    events in which apache has no hope of recovering).  In contrast,
    the module <CODE>init</CODE> function is passed a pool whose lifetime
    ends when the parent exits or restarts.

<DT><STRONG><CODE>child_terminate</CODE></STRONG>
<DD>Used in the child to indicate the child should exit after finishing
    the current request.

<DT><STRONG><CODE>register_other_child</CODE></STRONG>
<DD>See <CODE>http_main.h</CODE>.  This is used in the parent to register
    a child for monitoring.  The parent will report status to a supplied
    callback function.  This allows modules to create their own children
    which are monitored along with the httpd children.

<DT><STRONG><CODE>piped_log</CODE></STRONG>
<DD>See <CODE>http_log.h</CODE>.  This API provides the common code for
    implementing piped logs.  In particular it implements a reliable piped
    log on architectures supporting it (<EM>i.e.</EM>, Unix at the moment).

<DT><STRONG>scoreboard format changed</STRONG>
<DD>The scoreboard format is quite different.  It is considered a
    "private" interface in general, so it's only mentioned here as an FYI.

<DT><STRONG><CODE>set_last_modified</CODE> split into three</STRONG>
<DD>The old function <CODE>set_last_modified</CODE> performed multiple
    jobs including the setting of the <CODE>Last-Modified</CODE> header, the
    <CODE>ETag</CODE> header, and processing conditional requests (such as
    IMS).  These functions have been split into three functions:
    <CODE>set_last_modified</CODE>, <CODE>set_etag</CODE>, and
    <CODE>meets_conditions</CODE>.  The field <CODE>mtime</CODE> has been
    added to <CODE>request_rec</CODE> to facilitate
    <CODE>meets_conditions</CODE>.

<DT><STRONG>New error logging function: <CODE>ap_log_error</CODE></STRONG>
<DD>All old logging functions are deprecated, we are in the process of
    replacing them with a single function called <CODE>ap_log_error</CODE>.
    This is still a work in progress.

<DT><STRONG><CODE>set_file_slot</CODE> for config parsing</STRONG>
<DD>The <CODE>set_file_slot</CODE> routine provides a standard routine that
    prepends ServerRoot to non-absolute paths.

<DT><STRONG><CODE>post_read_request</CODE> module API</STRONG>
<DD>This request phase occurs immediately after reading the request (headers),
    and immediately after creating an internal redirect.  It is most useful
    for setting environment variables to affect future phases.

<DT><STRONG><CODE>psocket</CODE>, and <CODE>popendir</CODE></STRONG>
<DD>The <CODE>psocket</CODE> and <CODE>pclosesocket</CODE> functions allow
    for race-condition free socket creation with resource tracking.
    Similarly <CODE>popendir</CODE> and <CODE>pclosedir</CODE> protect
    directory reading.

<DT><STRONG><CODE>is_initial_req</CODE></STRONG>
<DD>Test if the request is the initial request (<EM>i.e.</EM>, the one
    coming from the client).

<DT><STRONG><CODE>kill_only_once</CODE></STRONG>
<DD>An option to <CODE>ap_spawn_child</CODE> functions which prevents Apache
    from aggressively trying to kill off the child.

<DT><STRONG><CODE>alloc debugging code</CODE></STRONG>
<DD>Defining <CODE>ALLOC_DEBUG</CODE> provides a rudimentary memory
    debugger which can be used on live servers with low impact --
    it sets all allocated and freed memory bytes to 0xa5.  Defining
    <CODE>ALLOC_USE_MALLOC</CODE> will cause the alloc code to use
    <CODE>malloc()</CODE> and <CODE>free()</CODE> for each object.  This
    is far more expensive and should only be used for testing with tools
    such as Electric Fence and Purify.  See <CODE>main/alloc.c</CODE>
    for more details.

<DT><STRONG><CODE>ap_cpystrn</CODE></STRONG>
<DD>The new <CODE>strncpy</CODE> "lookalike", with slightly different
    semantics is much faster than <CODE>strncpy</CODE> because it
    doesn't have to zero-fill the entire buffer.

<DT><STRONG><CODE>table_addn</CODE>, <CODE>table_setn</CODE>,
    <CODE>table_mergen</CODE></STRONG>
<DD>These new functions do <STRONG>not</STRONG> call <CODE>pstrdup</CODE>
    on their arguments.  This provides for big speedups.  There is
    also some debugging support to ensure code uses them properly.
    See <CODE>src/CHANGES</CODE> for more information.

<DT><STRONG><CODE>construct_url</CODE></STRONG>
<DD>The function prototype for this changed from taking a
    <CODE>server_rec *</CODE> to taking a <CODE>request_rec *</CODE>.

<DT><STRONG><CODE>get_server_name</CODE>, <CODE>get_server_port</CODE></STRONG>
<DD>These are wrappers which deal with the
    <A HREF="mod/core.html#usecanonicalname">UseCanonicalName</A> directive
    when retrieving the server name and port for a request.

<DT><STRONG>Change to prototype for <CODE>ap_bspawn_child</CODE> and
    <CODE>ap_call_exec</CODE></STRONG>
<DD>Added a <CODE>child_info *</CODE> to <CODE>spawn</CODE> function 
    (as passed to <CODE>ap_bspawn_child</CODE>) and to 
    <CODE>ap_call_exec</CODE> to allow children to work correctly on Win32.
    We also cleaned up the nomenclature a bit, replacing
    <CODE>spawn_child_err</CODE> with simply
    <CODE>ap_spawn_child</CODE> and <CODE>spawn_child_err_buff</CODE>
    with simply <CODE>ap_bspawn_child</CODE>.

<DT><STRONG><CODE>ap_add_version_component()</CODE></STRONG>
<DD>This API function allows for modules to add their own additional
    server tokens which are printed on the on the <CODE>Server:</CODE>
    header line. Previous 1.3beta versions had used a
    <CODE>SERVER_SUBVERSION</CODE> compile-time <CODE>#define</CODE>
    to perform this function. Whether the tokens are actually displayed
    is controlled by the new <CODE>ServerTokens</CODE> directive.

</DL>

<P><HR>

<H3><A NAME="misc">Miscellaneous Enhancements</A></H3>

<DL>
<DT><STRONG><A HREF="ebcdic.html">Port to EBCDIC mainframe machine
    running BS2000/OSD</A></STRONG>
<DD>As a premiere, this version of Apache comes with a beta version of
    a port to a mainframe machine which uses the EBCDIC character set
    as its native codeset (It is the SIEMENS family of mainframes
    running the BS2000/OSD operating system on a IBM/390
    compatible processor. This mainframe OS nowadays features a
    SVR4-like POSIX subsystem).

<DT><STRONG><A HREF="mod/core.html#accessfilename"><CODE>AccessFileName</CODE>
    Enhancement</A></STRONG>
<DD>The <CODE>AccessFileName</CODE> directive can now take more than
    one filename. This lets sites serving pages from network file
    systems and more than one Apache web server, configure access
    based on the server through which shared pages are being served.

<DT><STRONG><CODE>HostNameLookups</CODE> now defaults to "Off"</STRONG>
<DD>The <A
    HREF="mod/core.html#hostnamelookups"><CODE>HostNameLookups</CODE></A>
    directive now defaults to "Off". This means that, unless explicitly
    turned on, the server will not resolve IP addresses into names. This
    was done to spare the Internet from unnecessary DNS traffic.

<DT><STRONG>Double-Reverse DNS enforced</STRONG>
<DD>The <A
    HREF="mod/core.html#hostnamelookups"><CODE>HostnameLookups</CODE></A>
    directive now supports double-reverse DNS.  (Known as
    <EM>PARANOID</EM> in the terminology of tcp_wrappers.)  An IP
    address passes a double-reverse DNS test if the forward map of the
    reverse map includes the original IP.  Regardless of the
    HostnameLookups setting, <A
    HREF="mod/mod_access.html">mod_access</A> access lists using DNS
    names <STRONG>require</STRONG> all names to pass a double-reverse
    DNS test.  (Prior versions of Apache required a compile-time
    switch to enable double-reverse DNS.)

<DT><STRONG>LogLevel and syslog support</STRONG>
<DD>Apache now has <A HREF="mod/core.html#loglevel">configurable error
    logging levels</A> and supports <A
    HREF="mod/core.html#errorlog">error logging via syslogd(8)</A>.
    
<DT><STRONG>Detaching from stdin/out/err</STRONG>
<DD>On boot Apache will now detach from stdin, stdout, and stderr.  It
    does not detach from stderr until it has successfully read the
    config files.  So you will see errors in the config file.  This
    should make it easier to start Apache via rsh or crontab.

<DT><A NAME="y2k"><STRONG>Year-2000 Improvements</STRONG></A>
<DD>The default <CODE>timefmt</CODE> string used by <A
    HREF="mod/mod_include.html"><CODE>mod_include</CODE></A> has been
    modified to display the year using four digits rather than the
    two-digit format used previously.  The <A
    HREF="mod/mod_autoindex.html"><CODE>mod_autoindex</CODE></A>
    module has also been modified to display years using four digits
    in FancyIndexed directory listings.

<DT><STRONG>Common routines Moving to a Separate Library</STRONG>
<DD>There are a number of functions and routines that have been
    developed for the Apache project that supplement or supersede
    library routines that differ from one operating system to another.
    While most of these are used only by the Apache server itself,
    some are referenced by supporting applications (such as
    <CODE>htdigest</CODE>), and these other applications would fail to
    build because the routines were built only into the server.  These
    routines are now being migrated to a separate subdirectory and
    library so they can be used by other applications than just the
    server.  See the <CODE>src/ap/</CODE> subdirectory.

<DT><STRONG>New <CODE><A HREF="mod/core.html#serversignature">
    ServerSignature</A></CODE> directive</STRONG>
<DD>This directive optionally adds a line containing the server
    version and virtual host name to server-generated pages (error
    documents, ftp directory listings, mod_info output <EM>etc.</EM>). This
    makes it easier for users to tell which server produced the error
    message, especially in a proxy chain (often found in intranet
    environments).

<DT><STRONG>New <CODE><A HREF="mod/core.html#usecanonicalname">
    UseCanonicalName</A></CODE> directive</STRONG>
<DD>This directive gives control over how Apache creates
    self-referential URLs.  Previously Apache would always use the <A
    HREF="mod/core.html#servername"> ServerName</A> and <A
    HREF="mod/core.html#port">Port</A> directives to construct a
    "canonical" name for the server.  With <CODE>UseCanonicalName
    off</CODE> Apache will use the hostname and port supplied by the
    client, if available.

<DT><STRONG><CODE>SERVER_VERSION</CODE> definition abstracted, and server
    build date added</STRONG> 
<DD>In earlier versions, the Apache server version was available to
    modules through the <CODE>#define</CODE>d value for
    <CODE>SERVER_VERSION</CODE>.  In order to keep this value
    consistent when modules and the core server are compiled at
    different times, this information is now available through the
    core API routine <CODE>ap_get_server_version()</CODE>.  The use of
    the <CODE>SERVER_VERSION</CODE> symbol is deprecated.  Also,
    <CODE>ap_get_server_built()</CODE> returns a string representing
    the time the core server was linked.
 
<DT><A HREF="mod/core.html#servertokens"><STRONG>Including the operating 
    system in the server identity</STRONG></A><BR>
<DD>A new directive, <CODE>ServerTokens</CODE>, allows the Webmaster
    to change the value of the <CODE>Server</CODE> response header
    field which is sent back to clients.  The <CODE>ServerTokens</CODE>
    directive controls whether the server will include a non-specific
    note in the server identity about the type of operating system on
    which the server is running as well as included module information.
    As of Apache 1.3, this additional information is included by default.

</DL>

<DT><STRONG>Support for Netscape style SHA1 encrypted passwords</STRONG><BR>
<DD>To facilitate migration or integration of BasicAuth password
    schemes where the password is encrypted using SHA1 (as opposed
    to apache's build in MD5 and/or the OS specific crypt(3) function
    ) passwords prefixed with with <CODE>{SHA1}</CODE> are taken
    as Base64 encoded SHA1 passwords. More information and
    some utilities to convert Netscape ldap/ldif entries can be
    found in support/SHA1. 

<HR>
 <H3 ALIGN="CENTER">
  Apache HTTP Server Version 1.3
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