Ahh yes. Wise question Anonymous One. Perl is far beyond using function calls for this. Why use function calls when we have variables like $< and $> ?!?!

$< or $UID
"The real user ID of this process."

$>
$EUID
"The effective uid of this process"

Thus speaks the Holy Camel Book of Knowledge Light of the World.
so...

$< = $>   #set real to effective uid
($<,$>) = ($>,$<);   #swap real and effective uid
[download]

Obviously, these require you to be running setuid.Go and rejoice in your new learning.
---
crulx
crulx@iaxs.net