how to get common name using gid and uid

[Chris W. Parker]

hello,

given a gid or uid, how do i get the group name or user name
respectively? i'm doing this within php, but i will be executing
something via the cl and then storing the results. i know i can grep the
/etc/passwd and /etc/group files but i'd like to find out if there's a
better way.

can someone help me out with this?


thanks,
chris.