iTP Secure WebServer System Administrator's Guide (Version 7.0)

Using Common Gateway Interface (CGI) Programs
iTP Secure WebServer System Administrator’s Guide—523346-012
8-4
Pathway CGI Server Classes
Pathway CGI Server Classes
Pathway CGI server classes provides substantial improvement in performance by
comparison with conventional or generic-CGI, because the CGI program is
implemented not as a separate process, but as a user-written CGI_main procedure
within a NonStop TS/MP server process.
To create a Pathway CGI server class, you use the CGI library:
•
Use the following library routines, rather than the corresponding C library routines,
for access to the standard input, output, and error files:
°
CGI_fread
°
CGI_fwrite
°
CGI_printf
°
CGI_getc
°
CGI_puts
•
Use other CGI procedures as required by your application. Table 8-6 on page 8-30
lists and describes all the procedures in the CGI library.
The semantics of CGI routines are identical to the corresponding routines in the
standard C library.
•
Link your application code with the CGI library, libcgi.a, to create an executable
program.
The CGI library uses the context-sensitive Pathsend interface, as shown in Figure 8-3.
The Pathway CGI interface simulates the behavior of the OSS standard input, output,
and error files.
Note. If your program must read environment variables, write a CGI_initialize routine so that
when CGI_main is invoked, the getenv() call will return the WebServer’s environment
variables. See Design Guidelines
on page 8-33 for more information.
Note. Applications built using a version of libcgi.a that is newer than the version of the iTP
Secure WebServer (httpd process) might not run correctly in the older WebServer
environment. Applications built with a previous version of libcgi.a run correctly with newer
versions of the iTP Secure WebServer.
The iTP WebServer provides CGI library, which supports the IEEE floating-point (libcgi.a)
and Tandem floating-point (libcgi_tandem.a).
Note. CGI requests and replies can be of any length. For long requests and replies, the httpd
process and the process labeled “Pathway CGI main” exchange multiple Serverclass_send
and reply messages.