The WOPI FastCGI front-end, called ffalcgi is a stand-alone program (a binary executable for the target platform) which loads a Falcon script corresponding to its name.
The program is loaded by the web server (that must support the FastCGI library interface), and data is passed to it through the FastCGI library. As soon as the CGI program is ready, it searches for a falcon script bearing its same name (but having extension .fal, .ftd or .fam), loading and then executing it.
Except for the usage of the FastCGI library, this front end works as the CGI stand-alone front-end interface. Using FastCGI, the program is loaded once and stays resident in the web server application process hierarchy; this reduces script load time and allows this front-end to use advanced performance optimization techniques, as module caching.
Note: Be sure to read the Isomorphism of CGI based sites. documentation about specificities of the CGI model.
The CGI front-end reads the following attributes from the main module:
Other than that, you have to activate the ability to execute CGI programs from within the web server you're currently using. Check the documentation of the web server for further information.