oracle v$session equivalent in postgresql

This is a multi-part message in MIME format.

------=_NextPart_000_0011_01C4C311.5DA87D00
Content-Type: text/plain;
charset="US-ASCII"
Content-Transfer-Encoding: 7bit

I'm looking for the equivalent in postgresql to the v$session variables in
Oracle. In particular, I need to convert the following statement:



select s.program, s.machine into :New.app_name,:New.comp_name from v$session
s where s.audsid=userenv('SESSIONID');



Any help appreciated


------=_NextPart_000_0011_01C4C311.5DA87D00
Content-Type: text/html;
charset="US-ASCII"
Content-Transfer-Encoding: quoted-printable

xmlns:w=3D"urn:schemas-microsoft-com:office:word" =
xmlns=3D"http://www.w3.org/TR/REC-html40">


charset=3Dus-ascii">