#!/usr/bin/perl -w
#
# UNTESTED CODE
#

use strict;
use warnings;



open(FILE, "file.log") or die "$!";

my ($date,$found);
while(my $line = <FILE>){
  chomp;


  if (/^(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}).*$/){ # if match Date
    $date = $1;   # set DATE
  }elsif ( /1st search for a string/ ){ # if match what i want
    $found = $line;
  }


  if($found){
    print "$date:$found\n";
    $found = undef;
    $date = undef;
  }
}

close(FILE);
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