use Fcntl qw (:DEFAULT :flock :seek);

my $file = '/dev/shm/tmpcount.txt';
my $c;

do {
  if (-e $file) {
    $c = &fileread($file);
    die "C is empty" unless ($c);
    print "count is $c \n";
  } else { print "File not found\n"; }
} until ($c == 180);

sub fileread {																				 # Read using perl IO 
my $file = shift;
open(my $fh, "<", $file) || die "Can't open $file for reading: $!";
my $mode = LOCK_SH;
flock($fh,$mode) or die "couldn't lock";
my $string = do { local $/; <$fh> };
close $fh;
return $string;
}