mod_cgid Execution of CGI scripts using an external CGI daemon Base mod_cgid.c cgid_module Unix threaded MPMs only

Except for the optimizations and the additional ScriptSock directive noted below, mod_cgid behaves similarly to mod_cgi. See the mod_cgi summary for additional details about Apache and CGI.

On certain unix operating systems, forking a process from a multi-threaded server is a very expensive operation because the new process will replicate all the threads of the parent process. In order to avoid incurring this expense on each CGI invocation, mod_cgid creates an external daemon that is responsible for forking child processes to run CGI scripts. The main server communicates with this daemon using a unix domain socket.

This module is used by default instead of mod_cgi whenever a multi-threaded MPM is selected during the compilation process. At the user level, this module is identical in configuration and operation to mod_cgi. The only exception is the additional directive ScriptSock which gives the name of the socket to use for communication with the cgi daemon.

mod_cgi Running CGI programs under different user IDs ScriptLog ScriptLogLength ScriptLogBuffer ScriptSock The filename prefix of the socket to use for communication with the cgi daemon ScriptSock file-path ScriptSock logs/cgisock server config

This directive sets the filename prefix of the socket to use for communication with the CGI daemon, an extension corresponding to the process ID of the server will be appended. The socket will be opened using the permissions of the user who starts Apache (usually root). To maintain the security of communications with CGI scripts, it is important that no other user has permission to write in the directory where the socket is located.

Example ScriptSock /var/run/cgid.sock