What's wrong with my code?

You have several race conditions. You open the file. You have yet to apply the lock. Then you lock it. You read it then CLOSE THE FILE RELEASING THE LOCK BUT YOU HAVE NOT FINISHED! You then do stuff ;-) While you are doing this stuff any other program can open and lock the file.

There are many solutions but in essence you need a 'lock' that persists until you have completed the update. Ie LOCK, read, increment, write, UNLOCK. This is a rather well worn chestnut. Could I suggest Super Search Gotta go. I have a boarding call....

cheers

tachyon

In reply to Re: Safe Counter Follow Up by tachyon
in thread Safe Counter by Gorby

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