Appendix: Source files

In case you are interested in how CGI scripts can be written, or if you want to compare your attempt at the exercises with mine, here are the Perl files used to generate them.

• Environment example: Generates an HTML document listing the values of (most of) the current environment variables.
• The endless document: Displays one of the many(!) pages of a document with infinitely many pages. It uses the QUERY_STRING environment variable to see what page it should generate and what the previous page was. The first page can be found at http://agora.leeds.ac.uk/Perl-cgi/endless?1.
• &read_input: Just a Perl subroutine to translate URL-encoded information from the QUERY_STRING environment variable. It also handles the POST method transparently. This subroutine is a version of part of the cgi-lib.pl library of such routines.
• Serve tea: Tells you what drink you've ordered and that we've just sold out of your favourite cream cake (if any). It takes input from the Tea Sever.
• Text area example: Comments on the contents of a text area. It is triggered by the last example on the page about text areas and the POST method.