In the worst case you will get garbage. That's why there are functions to lock files or even parts of files. Basically every script tries to lock a file for itself, if that fails it waits and tries again. Whoever has the lock writes to the file and then releases the lock.

In reply to Re: Performing action on one file at same time by two perl scripts by jethro
in thread Performing action on one file at same time by two perl scripts by Anonymous Monk

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