Note:

if you 

open(FILE, ">testing")

[download]
you will truncate the file before you have it locked, this may not be what you want in a production system! Use 
open(FILE, ">>testing")

[download]
before you get the lock and then truncate() if you want to, er, truncate the file once its locked. Or lock a separate semaphore file who's contents are unimportant.

In reply to Re: How do I lock a file? by danstuken
in thread How do I lock a file? by vroom

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