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 ...
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.
Query options:
CC TARGET CFLAGS SBINDIR CFLAGS_SHLIB INCLUDEDIR LD_SHLIB LIBEXECDIR LDFLAGS_SHLIB SYSCONFDIR LIBS_SHLIB PREFIXUse this for manually determining settings. For instance use
INC=-I`apxs -q INCLUDEDIR`inside your own Makefiles if you need manual access to Ap