FastCGI (website archive ) is a language-independent protocol based on CGI. It improves performance (at the cost of isolation) by not creating a new process for every request. It competes with SCGI, which is more popular in Tcl-land.

Tcl packages

FastCGI for Tcl (C extension)

What FastCGI for Tcl
cvs -z3 -d:pserver:[email protected]:/cvsroot/tcl-fastcgi co -P tcl-fastcgi
Description A C extension for the Tcl interpreter that implement the FastCGI protocol. Works under Windows as well as *nix.
Requirements Tcl 8.3
Updated 2013-04-17
Authors Tom Poindexter, Christoph Bauer

Fcgi.tcl (pure Tcl)

What Fcgi.tcl
Description A fork of the pure Tcl implementation of FastCGI that used to be part of Tom Poindexter's project.
Requirements Tcl 8.0 (the library itself), Tcl 8.5 (examples)
Updated 2021-04
Authors Tom Poindexter; modifications by dbohdan

tclfcgi (C extension)

What tclfcgi
Description A Tcl wrapper for the FastCGI C library.
Requirements Tcl 8.6, Critcl 3
Updated 2013-02-04
Authors Jos Decoster

tcl-xcgi (pure Tcl)

What tcl-xcgi
Description Implements CGI, FastCGI, SCGI.
Requirements Tcl 8.5?
Updated 2021-01
Authors Sean Zhang


RLH 10-18-2006: I read a couple things that indicated there is going to be a push to refine and enhance FastCGI and include it with Apache. The idea is to get away from the mod_<language> and have FastCGI give everyone a robust even playing field. We shall see. Here is a link to the info: [L1 ]

ZLM 2008-12-28: Microsoft released FastCGI extensions for IIS 6 and 7. These can be downloaded from .

See also