use strict;
my $logdir=".";
opendir(LOGS, $logdir) or die ("Cant open $logdir");

my $pattern = '_log';
my @logfiles = grep /$pattern/,(readdir LOGS);
closedir(LOGS);

foreach my $file (sort @logfiles) {
  my $filename = $logdir . "/" . $file;
  open(LOG, $filename);
  my @line = <LOG>;
  if (my @hit = grep /I WANT TO GREP FROM IP.TXT/, @line) {
    chomp(@hit);
    print ("IP @hit is in file $file\n");
  }
}