apxs

apxs(8)                      System Manager's Manual                     apxs(8)



NAME
       apxs - APache eXtenSion tool

SYNOPSIS
       apxs -g [ -S variable=value ] -n name

       apxs -q [ -S variable=value ] query ...

       apxs -c [ -S variable=value ] [ -o dsofile ] [ -I incdir ] [ -D
       variable[=value] ] [ -L libdir ] [ -l libname ] [ -Wc,compiler-flags ] [
       -Wl,linker-flags ] files ...

       apxs -i [ -S variable=value ] [ -n name ] [ -a ] [ -A ] dsofile ...

       apxs -e [ -S variable=value ] [ -n name ] [ -a ] [ -A ] dsofile ...

DESCRIPTION
       apxs is a tool for building and installing extension modules for the
       Apache HyperText Transfer Protocol (HTTP) server. This is achieved by
       building a Dynamic Shared Object (DSO) from one or more source or object
       files which then can be loaded into the Apache server under runtime via
       the LoadModule directive from mod_so.

       So to use this extension mechanism, your platform has to support the DSO
       feature and your Apache httpd binary has to be built with the mod_so
       module.  The apxs tool automatically complains if this is not the case.
       You can check this yourself by manually running the command

         $ httpd -l

       The module mod_so should be part of the displayed list.  If these
       requirements are fulfilled, you can easily extend your Apache server's
       functionality by installing your own modules with the DSO mechanism by
       the help of this apxs tool:

         $ apxs -i -a -c mod_foo.c
         gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c
         ld -Bshareable -o mod_foo.so mod_foo.o
         cp mod_foo.so /path/to/apache/libexec/mod_foo.so
         chmod 755 /path/to/apache/libexec/mod_foo.so
         [activating module `foo' in /path/to/apache/etc/httpd.conf]
         $ apachectl restart
         /path/to/apache/sbin/apachectl restart: httpd not running, trying to start
         [Tue Mar 31 11:27:55 1998] [debug] mod_so.c(303): loaded module foo_module
         /path/to/apache/sbin/apachectl restart: httpd started
         $ _

       The arguments files can be any C source file (.c), a object file (.o) or
       even a library archive (.a). The apxs tool automatically recognizes these
       extensions and automatically uses the C source files for compilation
       while it just uses the object and archive files for the linking phase.
       But when using such pre-compiled objects, make sure they are compiled for
       Position Independend Code (PIC) to be able to use them for a DSO. For
       instance with GCC you always just have to use -fpic.  For other C
       compilers please consult its manual page or watch for the flags apxs uses
       to compile the object files.

       For more details about DSO support in Apache, first read the background
       information about DSO in htdocs/manual/dso.html, then read the
       documentation of mod_so.


OPTIONS
       Common options:

       -n name     This explicitly sets the module name for the -i (install) and
                   -g (template generation) option. Use this to explicitly
                   specify the module name.  For option -g this is required, for
                   option -i the apxs tool tries to determine the name from the
                   source or (as a fallback) at least by guessing it from the
                   filename.

       Query options:

       -q          Performs a query for apxs's knowledge about certain settings.
                   The query parameters can be one or more of the following
                   variable names:
                     CC              TARGET
                     CFLAGS          SBINDIR
                     CFLAGS_SHLIB    INCLUDEDIR
                     LD_SHLIB        LIBEXECDIR
                     LDFLAGS_SHLIB   SYSCONFDIR
                     LIBS_SHLIB      PREFIX
                   Use this for manually determining settings. For instance use
                     INC=-I`apxs -q INCLUDEDIR`
                   inside your own Makefiles if you need manual access to
                   Apache's C header files.

       Configuration options:

       -S variable=value
                   This option changes the apxs settings described above.

       Template Generation options:

       -g          This generates a subdirectory name (see option -n) and there
                   two files: A sample module source file named mod_name.c which
                   can be used as a template for creating your own modules or as
                   a quick start for playing with the apxs mechanism.  And a
                   corresponding Makefile for even easier building and
                   installing of this module.

       DSO compilation options:

       -c          This indicates the compilation operation. It first compiles
                   the C source files (.c) of files into corresponding object
                   files (.o) and then builds a DSO in dsofile by linking these
                   object files plus the remaining object files (.o and .a) of
                   files If no -o option is specified the output file is guessed
                   from the first filename in files and thus usually defaults to
                   mod_name.so

       -o dsofile  Explicitly specifies the filename of the created DSO file. If
                   not specified and the name cannot be guessed from the files
                   list, the fallback name mod_unknown.so is used.

       -D variable[=value]
                   This option is directly passed through to the compilation
                   command(s).  Use this to add your own defines to the build
                   process.

       -I incdir   This option is directly passed through to the compilation
                   command(s).  Use this to add your own include directories to
                   search to the build process.

       -L libdir   This option is directly passed through to the linker command.
                   Use this to add your own library directories to search to the
                   build process.

       -l libname  This option is directly passed through to the linker command.
                   Use this to add your own libraries to search to the build
                   process.

       -Wc,compiler-flags
                   This option passes compiler-flags as additional flags to the
                   compiler command.  Use this to add local compiler-specific
                   options.

       -Wl,linker-flags
                   This option passes linker-flags as additional flags to the
                   linker command.  Use this to add local linker-specific
                   options.

       DSO installation and configuration options:

       -i          This indicates the installation operation and installs one or
                   more DSOs into the server's libexec directory.

       -a          This activates the module by automatically adding a
                   corresponding LoadModule line to Apache's httpd.conf
                   configuration file, or by enabling it if it already exists.

       -A          Same as option -a but the created LoadModule directive is
                   prefixed with a hash sign (#), i.e. the module is just
                   prepared for later activation but initially disabled.

       -e          This indicates the editing operation, which can be used with
                   the -a and -A options similarly to the -i operation to edit
                   Apache's httpd.conf configuration file without attempting to
                   install the module.

EXAMPLES
       Assume you have an Apache module named mod_foo.c available which should
       extend Apache's server functionality. To accomplish this you first have
       to compile the C source into a DSO suitable for loading into the Apache
       server under runtime via the following command:

         $ apxs -c mod_foo.c
         gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c
         ld -Bshareable -o mod_foo.so mod_foo.o
         $ _

       Then you have to update the Apache configuration by making sure a
       LoadModule directive is present to load this DSO. To simplify this step
       apxs provides an automatic way to install the DSO in the "libexec"
       directory and updating the httpd.conf file accordingly. This can be
       achieved by running:

         $ apxs -i -a mod_foo.c
         cp mod_foo.so /path/to/apache/libexec/mod_foo.so
         chmod 755 /path/to/apache/libexec/mod_foo.so
         [activating module `foo' in /path/to/apache/etc/httpd.conf]
         $ _

       This way a line named

         LoadModule foo_module libexec/mod_foo.so

       is added to the configuration file if still not present.  If you want to
       have this operation to be disabled, use the -A option, i.e.

         $ apxs -i -A mod_foo.c

       For a quick test of the apxs mechanism you can create a sample Apache
       module template plus a corresponding Makefile via:

         $ apxs -g -n foo
         Creating [DIR]  foo
         Creating [FILE] foo/Makefile
         Creating [FILE] foo/mod_foo.c
         $ _

       Then you can immediately compile this sample module into a DSO and load
       it into the Apache server:

         $ cd foo
         $ make all reload
         apxs -c mod_foo.c
         gcc -fpic -DSHARED_MODULE -I/path/to/apache/include -c mod_foo.c
         ld -Bshareable -o mod_foo.so mod_foo.o
         apxs -i -a -n "foo" mod_foo.so
         cp mod_foo.so /path/to/apache/libexec/mod_foo.so
         chmod 755 /path/to/apache/libexec/mod_foo.so
         [activating module `foo' in /path/to/apache/etc/httpd.conf]
         apachectl restart
         /path/to/apache/sbin/apachectl restart: httpd not running, trying to start
         [Tue Mar 31 11:27:55 1998] [debug] mod_so.c(303): loaded module foo_module
         /path/to/apache/sbin/apachectl restart: httpd started
         $ _

       You can even use apxs to compile complex modules outside the Apache
       source tree, like PHP3, because apxs automatically recognized C source
       files and object files.

         $ cd php3
         $ ./configure --with-shared-apache=../apache-1.3
         $ apxs -c -o libphp3.so mod_php3.c libmodphp3-so.a
         gcc -fpic -DSHARED_MODULE -I/tmp/apache/include  -c mod_php3.c
         ld -Bshareable -o libphp3.so mod_php3.o libmodphp3-so.a
         $ _

       Only C source files are compiled while remaining object files are used
       for the linking phase.


SEE ALSO
       apachectl(1), httpd(8).



                                   April 1998                            apxs(8)