FastCGI interface for Tcl

Copyright 1998 Tom Poindexter, all rights reserved. Portions copyright 2021, 2024 D. Bohdan.

Fcgi.tcl is distributed under a BSD-style license like Tcl's own. See the file LICENSE.TERMS for details.

This is an updated document derived from the project's original readme.

What is Fcgi.tcl?

Fcgi.tcl is a Tcl interface for the FastCGI protocol. It is designed to work with Tcl 8 and 9.

Fcgi.tcl comes in two flavors:

• A Tcl source version that is written in 100% pure Tcl, optionally using the Extended Tcl (TclX) extension for certain types of FastCGI connections. This is what you will find in this repository.

• A Tcl C extension version, which uses library code from the FastCGI Developer's Kit. It is available elsewhere.

Each flavor provides the same programming interface for application programs. See the file INSTALL for more information about the two flavors.

FastCGI is a protocol to allow CGI-style programs to be started as a server, avoiding the CGI overhead of process creation and program loading. FastCGI servers can run on the same machine as your web server or on different machines. For more about FastCGI, see Wikipedia.

The FastCGI Developer's Kit from 1996 contained an interface for Tcl 7.4. Unfortunately, that interface was never updated for newer versions of Tcl. Fcgi.tcl was written to keep up with the latest Tcl releases.

Requirements

• Tcl 8.0 or later, including Tcl 9, for the library itself. Tcl 8.5 or later, including Tcl 9, for Fcgi::helpers and the tests.
• TclX (optional)
• A Web server that supports the FastCGI protocol:
  • Apache 2 with mod_fcgi
  • Caddy
  • H2O
  • Lighttpd with mod_fastcgi
  • Nginx with ngx_http_fastcgi_module
  • Any other server that supports FastCGI

Fcgi.tcl comes with automated tests that use Nginx. It has been manually tested with Caddy.

Installation

sudo make install

Make sure to add the directory you install Fcgi.tcl to to auto_path (for example, through TCLLIBPATH).

Documentation

See the man page for Fcgi.tcl and the NOTES file. An HTML, text, and PostScript version of the man page is in doc/. See also the example/ directory.

Known bugs

Fcgi.tcl has only been tested in the role of RESPONDER. Other FastCGI roles include AUTHORIZER and FILTER. They have not been tested.