iTP Secure WebServer System Administrator's Guide (iTPWebSvr 6.0+)

ManualsBrandsHP ManualsServerHP NonStop G-Series

201

202

203

204

205

206

207

208

209

210

Using Common Gateway Interface (CGI) Programs

iTP Secure WebServer System Administrator’s Guide—523346-002

8-4

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, as follows:

•

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 8-31

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.

Caution. 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 8-34 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.

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.