Here are two examples of a simple CGI script that displays a randomly selected image on a web page. The same script is presented here in C and perl, so that you can see how to implement scripts in either language.
You should put the executable C program (rand_images.cgi) and the perl script (rand_images.pl) in /usr/www/cgi-bin. Use chmod to make sure that both files have 755 permissions.
The images that they access are actually located in /usr/local/httpd/images. The web pages access the images in their local directory; the CGI script just figures out which one it wants to load.
To run these scripts from a web page, use the following HTML with SSI commands:
<H2>Here is a random image</H2> <P> Perl Script: <!--#exec cgi="rand_images.pl" --><BR> C Program: <!--#exec cgi="rand_images.cgi" --><BR>