It's quite possible that your browser does not send its user agent.

Also, what code you've shown is not a complete program, hence I cannot tell whether there is some other error. You should consider starting using CGI or CGI::Mini, which have the ->user_agent() method, which caters for other ways of passing the user agent around. For example, mod_perl likely doesn't set $ENV{HTTP_USER_AGENT}, because %ENV is process global and mod_perl can run in system threads.

In reply to Re^3: ENV variable by Corion
in thread ENV variable by irah

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