This may be a dumb question, but you mentioned:
There's definitely not a problem opening input_sequence.txt, because this is used successfully elsewhere in the program.
Did you forget to close the filehandle to input_sequence.txt or leave it (f)locked? I've been bitten by dumb mistakes like that before.

--

flounder

In reply to Re: system call not working by flounder99
in thread system call not working by Becky

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