I am not able to determine what exactly your problem is. From your first sentence I read: you have a given file name and want to find that file at a specific location (which I assume is a directory). If you just want that, you can use Perl's file test operator and avoid external calls to find and grep completely (see file test ops).

Like this

use strict;
use warnings;

if (-f '/pptai/nightly_db/data_loader_logs/2010-06-18_AIX_nightly_data
+_loader.log') {
  # file exists
  ...
} else {
  # file does not exist as a plain file
}
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If you want to check if the given file name is listed in a line of some other text file, you can use a simple loop for that. The file is read line by line until the file name is found or the text file has been read completely.

use strict;
use warnings;

my $searchstring = '/pptai/nightly_db/data_loader_logs';

open my $rfh, '<', '2010-06-18_AIX_nightly_data_loader.log' or die "ca
+nnot open file:$!\n";

while (defined($_ = <$rfh>)) {
   if (0 <= index $_, $searchstring) {
      # file name is part of the current line
      print ;
      last;
   }
}

close $rfh or die "cannot close:$!\n";
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