You are right that there is unnecessary disk access going on. There are cute/clever ways to do this (e.g. piping in from grep), but the easiest way would be swap your print statement with a concatenation: 

open my $FH, '<' , $config or die "Cannot open $config: $!\n";
my $data = <$FH>; # Dump the line
$data = '';
while (<$FH>) {
    next if /^\s*#|^$/;
    $data .= $_;
}
close $FH;
while ($data =~ m/\{([^}]*)\}/gx ) { 
    print "$1\n";
}

[download]
Incidentally, you have a $data = <$FH>; peppered into your first chunk. Are you meaning to dump the first line of the file? I've included that behavior, but it smells buggy to me.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Match pattern per line and after another one as multiline in single file opening by kennethk
in thread Match pattern per line and after another one as multiline in single file opening by Yakup

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