use strict;
use warnings;

my $out = "Backup/backup.txt";
my $logfile="log.txt";
my $MAL = '^"_.*"$';

my $logfile_new;

open LOG, "<", $logfile or die "Cannot open $logfile for read :$!";
open OUT, ">$out" or die "Cannot open $out for write :$!";

while ( <LOG> ) {
  if ( $_ =~ /$MAL/i ) {
  print OUT $_;
  }
}
[download]

Is it possible you don't have any matching lines?  Perhaps there's some whitespace at the beginning or end of the lines you want to match?

This regex will match whitespace at the beginning and end of the line:

# Find lines starting with "_ and ending with ", and containing option
+al
# leading or trailing whitespace.
#
my $MAL = '^\s*"_.*"\s*$';
[download]

If this still doesn't help you, try logging the lines which DON'T match:

use strict;
use warnings;

my $out     = "Backup/backup.txt";
my $out2    = "nomatch.txt";
my $logfile = "log.txt";
my $MAL = '^\s*"_.*"\s*$';

open LOG,  "<", $logfile or die "Cannot open $logfile for read :$!";
open OUT,  ">$out" or die "Cannot open $out for write :$!";
open OUT2, ">$out2" or die "Cannot open $out2 for write :$!";

while ( <LOG> ) {
  if ( $_ =~ /$MAL/i ) {
    print OUT $_;
  } else {
    print OUT2 $_;
  }
}
[download]

Then you can see if your logging mechanism is to blame, or whether there's some other reason that the lines you expect to match don't actually match, by checking what (if anything) gets written to "nomatch.txt".

---

s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/

OK, that really helps :) Basically, it's still not working correctly because it's still not matching anything (nomatch.txt holds a backup of the entire log.) However, I'm sure we can figure this out... I would like to match all strings in this document that start with "MAL_ and end with a single quote " I have this regex but it doesn't seem to be working:

my $MAL = '^\s*"MAL_.*"\s*$';
[download]

my $MAL = '^"_.*"$';
[download]

Is that what you want? ^ matchs the start of a line and $ matches the end. So this matches lines that only contain your string. As I read your spec, your string was only part of the line - in which case my solution might work better.

Update: Hmm... not sure why I'm being downvoted here as it looks to me like I'm pointing out the problem that liverpole spotted and fixed half an hour later. If someone could be polite enough to explain what they see as the problem then I'd appreciate it.

--


<http://dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg