Man, if your chat is supposed to be CGI, use FastCGI
or some equivalent so that you don't have to worry about process -time variables (vars that die with the program). Store the stuff in hashes. You can use mmap later to service multiple client in shared memory. Otherwise (or if you NEED to store this stuff in a file, tie this stuff into an AnyDB. (be careful of multiple servers accessing data- you will need data/file synchronization) Even a better solution may be to store cookies (use CGI;). There's probably a Q&A section somewhere on perlmonks that discusses CGI/HTML authentication (without webserver style auth). But the random number check wil serve you fine checking the cookie against a hash.
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