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<H1 ALIGN="CENTER">Module mod_so</H1>
<p>This module provides for loading of executable code and modules into the
server at start-up or restart time.</p>
<P><A
HREF="module-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base (Windows); Optional (Unix)
<BR>
<A
HREF="module-dict.html#SourceFile"
REL="Help"
<BR>
<A
HREF="module-dict.html#ModuleIdentifier"
REL="Help"
><STRONG>Module Identifier:</STRONG></A> so_module
<BR>
<A
HREF="module-dict.html#Compatibility"
REL="Help"
><STRONG>Compatibility:</STRONG></A> Available in Apache 1.3 and later.
</P>
<H2>Summary</H2>
<P>On selected operating systems this module can be used to load modules
into Apache at runtime via the <A HREF="/dso.html">Dynamic Shared
Object</A> (DSO) mechanism, rather than requiring a recompilation.
<P>
On Unix, the loaded code typically comes from shared object files
(usually with <SAMP>.so</SAMP> extension), on Windows this may either
the <SAMP>.so</SAMP> or <SAMP>.dll</SAMP> extension. This module is
only available in Apache 1.3 and up.
<p>In previous releases, the functionality of this module was provided
for Unix by mod_dld, and for Windows by mod_dll. On Windows, mod_dll
was used in beta release 1.3b1 through 1.3b5. mod_so combines these
two modules into a single module for all operating systems.
<P><STRONG> Warning: Apache 1.3 modules cannot be directly used with
Apache 2.0 - the module must be modified to dynamically load or
compile into Apache 2.0</STRONG>.</P>
<H2>Directives</H2>
<UL>
<LI><A HREF="#loadfile">LoadFile</A>
<LI><A HREF="#loadmodule">LoadModule</A>
</UL>
<H2><A NAME="creating">Creating Loadable Modules for Windows</A></H2>
<P><STRONG>Note: the module name format changed for Windows with Apache
1.3.15 and 2.0 - the modules are now named as mod_foo.so</STRONG>.
While mod_so still loads modules with ApacheModuleFoo.dll names, the
new naming convention is preferred; if you are converting your loadable
module for 2.0, please fix the name to this 2.0 convention.</P>
<P>The Apache module API is unchanged between the Unix and Windows
versions. Many modules will run on Windows with no or little change
from Unix, although others rely on aspects of the Unix architecture
which are not present in Windows, and will not work.</P>
<P>When a module does work, it can be added to the server in one of two
ways. As with Unix, it can be compiled into the server. Because Apache
for Windows does not have the <CODE>Configure</CODE> program of Apache
for Unix, the module's source file must be added to the ApacheCore
project file, and its symbols must be added to the
<P>The second way is to compile the module as a DLL, a shared library
that can be loaded into the server at runtime, using the
<CODE><A HREF="#loadmodule">LoadModule</A></CODE>
directive. These module DLLs can be distributed and run on any Apache
for Windows installation, without recompilation of the server.</P>
<P>To create a module DLL, a small change is necessary to the module's
source file: The module record must be exported from the DLL (which
will be created later; see below). To do this, add the <CODE
>AP_MODULE_DECLARE_DATA</CODE> (defined in the Apache header files)
to your module's module record definition. For example, if your module
has:</P>
<PRE>
module foo_module;
</PRE>
<P>Replace the above with:</P>
<PRE>
module AP_MODULE_DECLARE_DATA foo_module;
</PRE>
<P>Note that this will only be activated on Windows, so the module can
continue to be used, unchanged, with Unix if needed. Also, if you are
familiar with <CODE>.DEF</CODE> files, you can export the module
record with that method instead.</P>
<P>Now, create a DLL containing your module. You will need to link this
against the libhttpd.lib export library that is created when the
libhttpd.dll shared library is compiled. You may also have to change
the compiler settings to ensure that the Apache header files are
correctly located. You can find this library in your server root's
modules directory. It is best to grab an existing module .dsp file
from the tree to assure the build environment is configured correctly,
or alternately compare the compiler and link options to your .dsp.</P>
<P>This should create a DLL version of your module. Now simply place it
in the <SAMP>modules</SAMP> directory of your server root, and use
the <CODE><A HREF="#loadmodule">LoadModule</A></CODE> directive to
load it.</P>
<HR>
<H2><A NAME="loadfile">LoadFile</A> directive</H2>
<!--%plaintext <?INDEX {\tt LoadFile} directive> -->
<A
HREF="directive-dict.html#Syntax"
REL="Help"
><STRONG>Syntax:</STRONG></A> LoadFile <EM>filename</em>
[<em>filename</em>] ...<BR>
<A
HREF="directive-dict.html#Context"
REL="Help"
><STRONG>Context:</STRONG></A> server config<BR>
<A
HREF="directive-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base<BR>
<A
HREF="directive-dict.html#Module"
REL="Help"
><STRONG>Module:</STRONG></A> mod_so<P>
The LoadFile directive links in the named object files or libraries
when the server is started or restarted; this is used to load
additional code which may be required for some module to
work. <EM>Filename</EM> is either and absolute path or relative to <A
<H2><A NAME="loadmodule">LoadModule</A> directive</H2>
<!--%plaintext <?INDEX {\tt LoadModule} directive> -->
<A
HREF="directive-dict.html#Syntax"
REL="Help"
><STRONG>Syntax:</STRONG></A> LoadModule <EM>module filename</EM><BR>
<A
HREF="directive-dict.html#Context"
REL="Help"
><STRONG>Context:</STRONG></A> server config<BR>
<A
HREF="directive-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base<BR>
<A
HREF="directive-dict.html#Module"
REL="Help"
><STRONG>Module:</STRONG></A> mod_so<P>
The LoadModule directive links in the object file or library
<EM>filename</EM> and adds the module structure named <EM>module</EM>
to the list of active modules. <EM>Module</EM> is the name of the
external variable of type <CODE>module</CODE> in the file, and is
listed as the <a href="module-dict.html#ModuleIdentifier">Module
Identifier</a> in the module documentation. Example:
<BLOCKQUOTE><CODE>
LoadModule status_module modules/mod_status.so
</CODE></BLOCKQUOTE>
<P>loads the named module from the modules subdirectory of the
ServerRoot.<P>
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