I'd like to have a script that breaks a large file into multiple files. Basicaly, the script reads a large file and looking for a line "PJL EOJ", if line found, the counter will count it as 1, so when counter is up to 2000, the script should open a new file, and write the rest data into the new file, and so on so on. Can someone help me on this script? Thanks.

Try split or csplit.

Here's a Perl script. note: posting code at this site is a pain in the ass! replace each @ with lt sign replace each % with gt sign #!/usr/bin/perl $source = $ARGV[0]; # passed via command line $num = '001'; $dest = 'file'; $count = 0; open FH, "@ $source" or die "could not open $source : $!"; open OUT, "% $dest$num.txt" or die "could not open $dest : $!"; while (@FH%) { if ($count == 2000) { $num++; $count = 0; open OUT, "% $dest$num.txt" or die "could not open $dest$num.txt : $!"; } print OUT; $count++ if (/PJL EOJ/); } close FH; close OUT;