Detecting and Reporting Errors

Several things may go wrong in any program, including problems in programming, bad or missing input, unreachable external resources, and many other things. Perl doesn’t have any built-in error handling. It knows when it couldn’t do something, and it can tell me about errors, but it’s up to me as the Perl programmer to ensure that my program does the right thing, and when it can’t, try to do something useful about it.