Since you mentioned CGI (thus, CGI app writing), it is extremely important to return some error code and message to the user/browser (this is called "user-friendliness"). This is not so intuitive until you use CGI::Carp or better yet, you own personalized error message system which fits in with the theme of the rest of the site. The problem I see with global variables is that they become to cluttery and are named differently for every module. I find function return codes far more useful and clear. Plus, you can put the whole shebang in the same statement! 
die "Oops!\n" unless evilfunction(); #or "if", if you prefer

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I suppose the use of the global vars carried over from C when you were basically stuck returning static variables for multi-variant-byte length information. Of course, Perl does not have this restriction and thus would recommend using returns. My favorite scheme is 0 for success, some string or number on failure- preferably something I might be able to output to the user. This is definitely that something that has come with me from my UN*X C background (POSIX likes to make success 0 now).
AgentM Systems nor Nasca Enterprises nor Bone::Easy nor Macperl is responsible for the comments made by AgentM. Remember, you can build any logical system with NOR.

In reply to Re: Re: The art of error handling by AgentM
in thread The art of error handling by markjugg

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