my $in16S = '/Users/saierlab/db/all_16S_rRNA.faa';
open (I16S,"$in16S");
my $inList = 'no';
my $genus16S = '';
while(<I16S>) {

[download]

You should verify that open worked correctly before trying to use an invalid filehandle: 

my $in16S = '/Users/saierlab/db/all_16S_rRNA.faa';
open I16S, '<', $in16S or die "Cannot open '$in16S' because: $!";
my $inList = 'no';
my $genus16S = '';
while ( <I16S> ) {

[download]

In reply to Re: readline on closed filehandle error by jwkrahn
in thread readline on closed filehandle error by Oapples

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