Check out perldoc -f sysopen:

In many systems the "O_EXCL" flag is available for opening files in exclusive mode. This is not locking: exclusiveness means here that if the file already exists, sysopen() fails.
You probably should be locking the file. See perldoc -f flock

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: Exclusive open for append by jeffa
in thread Exclusive open for append by gri6507

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