Inconsistent memory statistics from ps

[Mark Benard]

I just noticed that ps (under OSx4.4) gives different figures for
memory usage depending on whether you use the -u or the -v option.
I am referring to the SIZE (virtual memory size) and RSS (real memory
usage) statistics for a process.  For example, if I look at a rlogin
process using ps -u, it shows SIZE=144 and RSS=50.  If I use ps -v,
I get SIZE=84 and RSS=36 for the same process.

Which of these figure are 'correct' and why is there a difference?
-- 
Mark Benard
Department of Computer Science     INTERNET & BITNET: mb at cs.tulane.edu
Tulane University                  USENET:   [{ames,bionet}!]rex!mb
New Orleans, LA 70118