The fix presented in the bug report is not nice. It uses the my $var if ..., discussed for example in Conditional initialization of my-variables.

It would've been cleaner to use something like 

                || die qq/Cannot open pid file "$self->{path}": $!\n/;
        flock($fh, LOCK_EX | LOCK_NB)
         || die qq/pid "$self->{path}" already locked: $!\n/;
-       my ($pid) = <$fh> =~ /^(\d+)/;
+       my $maybe = <$fh>;
+       $maybe = "" unless defined $maybe;
+       my ($pid) = $maybe =~ /^(\d+)/;
        close $fh if @_ == 1;

[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re^2: Undefined value returned on call to readline (<>)? by choroba
in thread Undefined value returned on call to readline (<>)? by Intrepid

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