use strict;
use warnings;

@ARGV == 1
  or die("Usage: $0 FILE\n");

my $in = shift;
open(INFILE, '<', $in)
   or die("Can't open $in for reading: $!\n");

while (<INFILE>) {
  chomp;
  for my $char (split //) {
    my $ord = ord($char);
    if (  $ord < 9
       || ($ord > 10 && $old < 32)
       || $ord > 126
    ) {
      print("$in contains illegal character \(ord:\ ", "$ord\) on line $.\n");
    }
  }
}