my $os_says = '';
my $pl_says = '';

if ( open FH, '/home/foo/bar.csh' ) {
  while (<FH>) {
    # no warnings;
    eval { $os_says .= `$_` }; # <- Fixed. Thanks Roger!
    if ($@) { $pl_says .= $@ } 
  }
  print "OS says: $os_says \n";
  print "Perl says: $pl_says \n";
}