I'd guess that there's no use POSIX; in the snippet. POSIX.pm is where the O_WRONLY, O_TRUNC and O_CREAT constants are defined.

If my guess is right, you also need to use strict; and use warnings; (see Use strict warnings and diagnostics or die for a good discussion of this), which would point you to the real error - the barewords, O_*.

Update: Strike obviously incorrect info

In reply to Re: open vs. sysopen by jsprat
in thread open vs. sysopen by sheep

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