Would I be correct in inferring from your code that the "account number" is always at the start of the filename and followed by an underscore? In that case, a simple index test would do (and I think should be pretty efficient). Something like this:

#!/usr/bin/perl

use strict;
use warnings;

my $filename = "000231263444_01_XY_20130110_061717.txt";
my $accountnumber = '000231263444';

if (index($filename, "${accountnumber}_") == 0) {
  print "Found\n";
} else {
  print "Not found\n";
}

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In reply to Re: Checking number in file name by hippo
in thread Checking number in file name by Anonymous Monk

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