[GENERAL] Getting linux $USER (and perhaps other env vars) in PL/pg-sql?

[Gauthier, Dave]

Hi:

Running 8.3.4 on Linux.

>From inside a stored procedure, is there a way to capture the linux user 
>(environment var = $USER) that is attached to the DB?

A simplistic (though meaningless) example would be echo $USER from something 
like "select get_linux_user()".

Thanks
-dave