class type cgi = object .. end
The usual 
Netcgi.cgi class with FCGI specific methods.
Inherits
method role : [ `Authorizer | `Filter | `Responder ]
A FastCGI application can fulfill each of the following three
	roles:
- `Responder: This is the usual role.  In this case the
	application is expected to act like a CGI program: It receives
	all the information associated with an HTTP request and
	generates an HTTP response.
- `Authorizer: An Authorizer FastCGI application receives
        all the information associated with an HTTP request and
        generates an authorized/unauthorized decision.
- `Filter: A Filter FastCGI application receives all the
        information associated with an HTTP request, plus an extra
        stream of data from a file stored on the Web server, and
        generates a "filtered" version of the data stream as an HTTP
        response.
method data : Netchannels.in_obj_channel
This the the channel on which the filter data is available.
	All methods of the object raise 
Netchannels.Closed_channel
	if the role is not 
`Filter.
method data_length : int
How many bytes of the data are available.
method data_mtime : float
The data last modification time, expressed as an integer
	number of seconds since the epoch (January 1, 1970 UTC).