The answer comes from the Perl in a Nutshell book, probably the bestest desk top book for perl, p.53.

One of the really neatest things about perl in general is all of the nifty special variables. If you want longer easier to read variables try useing the English.pm modual. Though i would caution because it may be the case that you are working on a system that doesn't have it, and your in the ugly position of not being able to install it. That would suck. 

$real_uid = $<;
$effective_uid = $>;

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little_mistress@mainhall.com

In reply to RE: getting the real and effective UIDs of current process by little_mistress
in thread getting the real and effective UIDs of current process by greatnorthern

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