Hello Wise Monks. I've been having trouble with the following code especially when several people run my script at the same time. What happens is that sometimes, when I view the file named "counter", it reflects a number lower than what it was the previous day, perhaps because the file was deleted somehow. But I don't see any way the file would be deleted. Please help? 
sub get_lock
{
  open(SEM, ">$semaphore_file") || die "Cannot create semaphore $semap
+hore_file: $!";
  flock(SEM, LOCK_EX) || die "Lock failed: $!";
}
sub release_lock
{
  close(SEM);
}
sub readdata
{
  my @filedata;         @filedata=();
  open(MFILE, ">>$completeadd") || die "file open2 failed at $complete
+add: $!\n";
  close(MFILE);
  open(MFILE, "$completeadd") || die "file open81 failed: $!\n";
  @filedata=<MFILE>;
  chomp @filedata;
  close(MFILE);
  return(@filedata);
}
sub writedata
{
  my @filedata;         @filedata=();

  @filedata=@_;
  open(MFILE, ">$completeadd") || die "file open3 failed: $!\n";
  foreach(@filedata)
  {
    print MFILE "$_\n";
  }
  close(MFILE);
}



$completeadd = "counter";
$semaphore_file = "counterLOCK";
get_lock();
if (-e $completeadd)
{
  open(MFILE, "$completeadd") || die "file open4 failed: $!\n";
  @filedata1=<MFILE>;
  chomp @filedata1;
  close(MFILE);
}
else
{
  @filedata1=readdata();
}
$hitcount=$filedata1[0];
if ($hitcount)
{
  $hitcount=$hitcount + 1;
}
else
{
  $hitcount = 1;
}
$filedata1[0]=$hitcount;
writedata(@filedata1);
release_lock();

close(CNTLCK);

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In reply to Disappearing File by Gorby

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