Whether you're using a cloned version of UNIX or the real thing, file locking does not prevent another process from modifying the file. File locks on UNIXish operating systems are advisory. See flock(2). The documentation also documents that locking over NFS does not work.

On Windows, you cannot overwrite a locked file. Maybe that is what you're thinking of?

In reply to Re: (OT) Question on flock by Corion
in thread (OT) Question on flock by kprasanna_79

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