There are multiple problems with this snippet.

1. This code will usually abend with throw a warning of an undefined value passed to chomp!
2. The last line of the file can be missed if its not terminated by \n.

What while (chomp (my $line = <$fh>)){} means is execute the while code if chomp is successful in removing at least 1 character from $line.

Assuming that the last line is terminated properly, after all data is read from the filehandle, $line will be undefined. chomp won't like that and will barf.

Now if the last line of the file is not terminated, an even more insidious thing can happen. That last line will be ignored because chomp does not remove any characters from that line.

So, don't use this construct.
here is proof:

use strict;
use warnings;
$|=1;

my $data = <<END;
asdf fjfjf
324
0
2345
2wefrwef
END

#chomp $data; #toggle on/off to see results

open my $fh, "<", \$data or die "$!";

while (chomp (my $line = <$fh>))
{
    print $line;
}

__END__
asdf fjfjf324023452wefrwefUse of uninitialized value $line in chomp at
+ testchompWhile.pl line 15, <$fh> line 5.
asdf fjfjf32402345
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