You opened PASSFAIL for output. If you want to read from it, you must open it for reading. Do so after invoking system(), or the file will not yet exist, and the open will fail. As others have noted, it's always wise to check the results of open() and log an error message if it fails.

In reply to Re: "Use of uninitialized value" even though the value is defined by jpl
in thread "Use of uninitialized value" even though the value is defined by mandrake00

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