You don't check for errors so it's likely that opening the file failed and you didn't notice.

Either use the autodie pragma at the top of your file:

use autodie;

[download]

... or manually check for failure:

open PROTEINFILE, $proteinfilename
    or die "Couldn't open '$proteinfilename': $!";

[download]

In reply to Re: Cannot open file in Strawberry Perl by Corion
in thread Cannot open file in Strawberry Perl by Anonymous Monk

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