Hi, I've seen a few similar problems to this posted here recently but none of them cover what I need to do and my Perl isn't strong enough yet for me to figure out how to do this.
I'm parsing a number of text files (can range in size from 1K upto 100M) where the record size of each line is variable. I need to find (or seek to ?) the last occurence of a pattern then apply some further parsing logic from that point on until the end of file.
What I do now (which doesn't cope with the problem) is 
$foundit = 0;
while (<$FH>) {
    $foundit = 1 if /^pattern/;
}

if ($foundit) {
    do some processing
}

[download]
This was working ok until I started to get multiple occurences of the pattern ,the files I'm parsing are now appended to rather than overwritten :(
I had an idea of making two passes on each file to be parsed. The first pass to ascertain how many occurences of pattern were in the file (set a count). The second to start parsing when the count was hit. e.g. 
open FH,"file" or die "Can't open file : $!\n";
$count1 = 0;
while (<$FH>) {

$count++ if /^pattern/;
}
close FH; 
open FH,"file" or die "Can't open file : $!\n";
$count2 = 0;
while (<$FH>) {
   if (/^pattern/ and $count2 < $count1) {
       $count2++;
   } else {
       do some processing
   }
}

[download]
This is a possibility but it's very slow, which is why I wonder whether anybody has some other ideas about how to do this more efficiently ?

In reply to parse from last occurence of pattern match by Anonymous Monk

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