


APXS2(8)                      apxs2                      APXS2(8)


NAME
       apxs2 - APache eXtenSion tool


SYNOPSIS
       apxs2 -g [ -S name=value ] -n modname


       apxs2 -q [ -S name=value ] query ...


       apxs2 -c [ -S name=value ] [ -o dsofile ] [ -I incdir ] [ -D name=value
       ] [ -L libdir ] [ -l libname ] [  -Wc,compiler-flags  ]  [  -Wl,linker-
       flags ] files ...


       apxs2 -i [ -S name=value ] [ -n modname ] [ -a ] [ -A ] dso-file ...


       apxs2 -e [ -S name=value ] [ -n modname ] [ -a ] [ -A ] dso-file ...



SUMMARY
       apxs2  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 run-
       time via the LoadModule directive from mod_so.


       So to use this extension mechanism your platform has to support the DSO
       feature and your Apache httpd2 binary has to be built with  the  mod_so
       module. The apxs2 tool automatically complains if this is not the case.
       You can check this yourself by manually running the command


             $ httpd2 -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 apxs2 tool:


             $ apxs2 -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/httpd2.conf]
             $ apachectl2 restart



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APXS2(8)                      apxs2                      APXS2(8)


             /path/to/apache/sbin/apachectl2 restart: httpd2 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/apachectl2 restart: httpd2 started
             $ _



       The  arguments  files can be any C source file (.c), a object file (.o)
       or even a library archive (.a). The apxs2 tool automatically recognizes
       these extensions and automatically used the C source files for compila-
       tion while just using the object and  archive  files  for  the  linking
       phase. But when using such pre-compiled objects make sure they are com-
       piled 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 compilers consult its manual page or  at
       watch for the flags apxs2 uses to compile the object files.


       For  more details about DSO support in Apache read the documentation 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
              apxs2 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 apxs2's knowledge about certain settings.
              The query parameters  can  be  one  or  more  of  the  following
              strings:   CC,   CFLAGS,   CFLAGS_SHLIB,  INCLUDEDIR,  LD_SHLIB,
              LDFLAGS_SHLIB, LIBEXECDIR, LIBS_SHLIB, SBINDIR, SYSCONFDIR, TAR-
              GET.  .PP  Use  this  for  manually  determining  settings.  For
              instance use INC=-I`apxs2 -q INCLUDEDIR`  .PP  inside  your  own
              Makefiles  if you need manual access to Apache's C header files.


   Configuration Options
       -S name=value
              This option changes the apxs2 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 apxs2 mechanism. And a corresponding



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APXS2(8)                      apxs2                      APXS2(8)


              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 usually
              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  com-
              mand(s).  Use this to add your own defines to the build process.

       -I incdir
              This option is directly passed through to the  compilation  com-
              mand(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 pro-
              cess.

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

       -Wl,linker-flags
              This option passes  linker-flags  as  additional  flags  to  the
              libtool  --mode=link  command. Use this to add local linker-spe-
              cific 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 direc-
              tory.

       -a     This activates the module by automatically adding a  correspond-
              ing  LoadModule line to Apache's httpd2.conf configuration file,



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APXS2(8)                      apxs2                      APXS2(8)


              or by enabling it if it already exists.

       -A     Same as option -a but the created LoadModule directive  is  pre-
              fixed  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
              httpd2.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 shared object suitable for loading into
       the Apache server under runtime via the following command:


             $ apxs2 -c mod_foo.c
             /path/to/libtool --mode=compile gcc ... -c mod_foo.c
             /path/to/libtool --mode=link gcc ... -o mod_foo.la mod_foo.slo
             $ _



       Then you have to update the Apache configuration by making sure a Load-
       Module  directive  is  present  to load this shared object. To simplify
       this step apxs2 provides an automatic way to install the shared  object
       in  its  "modules"  directory and updating the httpd2.conf file accord-
       ingly. This can be achieved by running:


             $ apxs2 -i -a mod_foo.la
             /path/to/instdso.sh mod_foo.la /path/to/apache/modules
             /path/to/libtool --mode=install cp mod_foo.la /path/to/apache/modules
             ...
             chmod 755 /path/to/apache/modules/mod_foo.so
             [activating module `foo' in /path/to/apache/conf/httpd2.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.





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APXS2(8)                      apxs2                      APXS2(8)


             $ apxs2 -i -A mod_foo.c



       For  a quick test of the apxs2 mechanism you can create a sample Apache
       module template plus a corresponding Makefile via:


             $ apxs2 -g -n foo
             Creating [DIR]  foo
             Creating [FILE] foo/Makefile
             Creating [FILE] foo/modules.mk
             Creating [FILE] foo/mod_foo.c
             Creating [FILE] foo/.deps
             $ _



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


             $ cd foo
             $ make all reload
             apxs2 -c mod_foo.c
             /path/to/libtool --mode=compile gcc ... -c mod_foo.c
             /path/to/libtool --mode=link gcc ... -o mod_foo.la mod_foo.slo
             apxs2 -i -a -n "foo" mod_foo.la
             /path/to/instdso.sh mod_foo.la /path/to/apache/modules
             /path/to/libtool --mode=install cp mod_foo.la /path/to/apache/modules
             ...
             chmod 755 /path/to/apache/modules/mod_foo.so
             [activating module `foo' in /path/to/apache/conf/httpd2.conf]
             apachectl2 restart
             /path/to/apache/sbin/apachectl2 restart: httpd2 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/apachectl2 restart: httpd2 started
             $ _



















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