# Manual Page: apxs

    NAME
         apxs - APache eXtenSion tool

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

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

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

         apxs -i [ -S name=value ] [ -n modname ] [ -a ] [ -A ]  dso-
         file ...

         apxs -e [ -S name=value ] [ -n modname ] [ -a ] [ -A ]  dso-
         file ...

    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  LoadMo-
         dule directive from mod_so.

         So to use this extension mechanism your platform has to sup-
         port  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 your-
         self 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/modules/mod_foo.so
           chmod 755 /path/to/apache/modules/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
         used the C source files for compilation while just using the
         object and archive files for the  linking  phase.  But  when
         using  such pre-compiled objects make sure they are compiled
         for position independent code (PIC) to be able to  use  them
         for  a  dynamically loaded shared object.  For instance with
         GCC you always just have to use -fpic.   For  other  C  com-
         pilers  consult  its  manual  page or at watch for the flags
         apxs uses to compile the object files.

         For more details about DSO support in Apache read the  docu-
         mentation    of    mod_so   or   perhaps   even   read   the
         src/modules/standard/mod_so.c source file.

    OPTIONS
         Common options:

         -n modname  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 guess-
                     ing it from the filename.

         Query options:

         -q          Performs a query for apxs's knowledge about cer-
                     tain  settings.  The query parameters can be one
                     or more of the following strings:
                       CC              TARGET
                       CFLAGS          SBINDIR
                       CFLAGS_SHLIB    INCLUDEDIR
                       LD_SHLIB        LIBEXECDIR
                       LDFLAGS_SHLIB   SYSCONFDIR
                       LIBS_SHLIB
                     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 name=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
                     build 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 dynamically shared object 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 usu-
                     ally defaults to mod_name.so

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

         -D name=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  pro-
                     cess.

         -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 dynamically shared objects
                     into the server's modules 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 accom-
         plish this you first have to compile the  C  source  into  a
         shared  object  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 shared
         object. To simplify this step apxs provides an automatic way
         to  install the shared object in its "modules" 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/modules/mod_foo.so
           chmod 755 /path/to/apache/modules/mod_foo.so
           [activating module `foo' in /path/to/apache/etc/httpd.conf]
           $ _

         This way a line named

           LoadModule foo_module modules/mod_foo.so

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

           $ apxs -i -A mod_foo.c

         For a quick test of the APXS mechanism you can create a sam-
         ple  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
         shared object 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/modules/mod_foo.so
           chmod 755 /path/to/apache/modules/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:

           $ 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
           $ _

         because apxs automatically recognized  C  source  files  and
         object  files.   Only  C  source  files  are  compiled while
         remaining object files are used for the linking phase.

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