Is it possible to do something like find -perm g=u? I say "like" because -perm mode requires mode to specify all the bits, not just g, and because I can't put u on the right side of the =, like I can with the chmod command:

you can specify exactly one of the letters ugo: the permissions granted
to  the  user  who  owns the file (u), the permissions granted to other
users who are members of the file's  group  (g),  and  the  permissions
granted  to  users  that are in neither of the two preceding categories
(o).

At the moment, I'm doing find | xargs -d \\n ls -lartd | egrep '^.(...)\1 which is just ugly.

Thanks.