Consider raising an exception (with die) when the error happens. Using the return value of a sub for both data and error signalling tends to always have this problem: using exceptions makes error conditions out-of-band and lets you treat the error when it's most convenient for you.

I was about to give an example, but then I realized I don't understand what myfunction() is doing and who opens FILEHANDLE.

In reply to Re: return undef by gaal
in thread return undef by dwijew

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