Hello Monks

I'm working on making the unix saved id c functions available in perl. (See Unix::SavedIDs.) The c interface when setting id values is:

setresuid(ruid,euid,suid);

[download]

I would like to accommodate the situation where a user only wants to set the suid, IE I want this to work:

setresuid(undef,undef,$suid);

[download]

But XS seems to take a bleak view of sending undef as a parameter. I can set default values, so:

setresuid($ruid,$euid)

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Works, but that doesn't help the instance where someone specifically passes undef as an arg.

The C functions accept '-1' to leave a value unchanged, so what I need to do is change undef to -1. I'd rather not require my users to say '-1' in a perl script where the perlish thing to do would be to say undef.

Thanks!
--Pileofrogs

In reply to Passing undef to XSUB by pileofrogs

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