NAME
     cgi-fcgi   - bridge from CGI to FastCGI

SYNOPSIS
     cgi-fcgi -f cmdPath
     cgi-fcgi -bind  -connect connName
     cgi-fcgi -start -connect connName appPath [nServers]
     cgi-fcgi -connect connName appPath [nServers]

DESCRIPTION
     cgi-fcgi is a CGI/1.1 program that communicates with an
     already-running FastCGI application in order to respond to an
     HTTP request.  cgi-fcgi is also capable of starting a FastCGI
     application.

     When you invoke cgi-fcgi as

         cgi-fcgi -f cmdPath

     then cgi-fcgi opens the file at cmdPath and reads its
     arguments from that file.  cgi-fcgi will skip lines
     that begin with the comment character #.  The first
     non-comment line should contain valid arguments in
     one of the other three forms.

     The -f form of cgi-fcgi is designed for Unix systems
     whose exec(2) family of system calls supports the execution of
     command interpreter files.  For instance, if a file with
     execute permission contains the text

         #! /bin/cgi-fcgi -f
         -connect /httpd/root/sock/app /httpd/root/bin/app

     the effect is the same as executing

         /bin/cgi-fcgi -connect /httpd/root/sock/app /httpd/root/bin/app

     When you invoke cgi-fcgi as

         cgi-fcgi -bind -connect connName

     the connName argument is either the path name of a Unix domain
     listening socket or a host:port pair.  If connName contains
     a colon, it is assumed to be host:port.  cgi-fcgi performs
     a connect(2) using connName.  If the connect succeeds, cgi-fcgi
     forwards the CGI environment variables and stdin data to the
     FastCGI application, and forwards the stdout and stderr data from
     the application to cgi-fcgi's stdout (most likely connected to
     a Web server).  When the FastCGI application signals the end of
     its response, cgi-fcgi flushes its buffers and
     exits, and the Web server completes the http response.

     When you invoke cgi-fcgi as

         cgi-fcgi -start -connect connName appPath [nServers]

     then cgi-fcgi performs the function of starting one or more
     FastCGI application processes.  The connName argument specifies
     either the path name of the Unix domain listening socket that
     cgi-fcgi will create, or is "localhost:NNN" where NNN is the port
     number of the TCP/IP listening socket that cgi-fcgi will create
     on the local machine.  (cgi-fcgi will not create processes
     on remote machines.)  After cgi-fcgi creates the listening socket,
     it forks nServers copies of a process running the executable file
     appPath.  If nServers is omitted, the effect is as if the value "1"
     had been specified.  The processes share the single listening socket.

     When you invoke cgi-fcgi as

         cgi-fcgi -connect connName appPath [nServers]
    
     cgi-fcgi performs -bind and then, if necssary, performs -start
     and repeats the -bind.  That is, cgi-fcgi first operates as if
     the command had been

         cgi-fcgi -bind -connect connName

     If the connect fails, cgi-fcgi tries

         cgi-fcgi -start -connect connName appPath [nServers]

     and finally retries

         cgi-fcgi -bind -connect connName

     In this form, cgi-fcgi does not support TCP/IP connections.
     
ENVIRONMENT VARIABLES
     The usual CGI ones, but they are not interpreted by cgi-fcgi.

SEE ALSO
     FGCI_accept(3)

BUGS
     cgi-fcgi doesn't generate useful HTTP responses in case of error,
     and it generates no response at all when run as start-fcgi.

     On Digital UNIX 3.0 systems the implementation of Unix Domain
     sockets does not work when such sockets are stored on NFS file
     systems.  Symptom: cgi-fcgi may core dump or may exit with
     status 38.  Work-around: store sockets in local file systems
     (/tmp often works) or use TCP/IP.

     On AIX systems the implementation of listening sockets
     does not support socket sharing, and the standard FastCGI
     application libraries can't synchronize access to AIX listening
     sockets.  Work-around: Don't use the nServers argument on AIX.

HISTORY
     Copyright (c) 1996 Open Market, Inc.
     See the file "LICENSE" for information on usage and redistribution
     of this file, and for a DISCLAIMER OF ALL WARRANTIES.
     $Id: cgi-fcgi.1,v 1.1.1.1 1997/09/16 15:36:26 stanleyg Exp $
