OSX: Adding new user on 10.6

dscl . -create /Users/username
dscl . -create /Users/username UserShell /usr/bin/false
dscl . -create /Users/username RealName "User description"
dscl . -create /Users/username UniqueID ###
dscl . -create /Users/username PrimaryGroupID ###
dscl . -create /Users/username NFSHomeDirectory /dev/null
dscl . -passwd /Users/username PASSWORD

view users' full configs:

dscacheutil -q user

view particular user's full config:

dscacheutil -q user -a name username

view user's uid only:

dscl . list /Users uid

view group's gid only:

dscl . list groups gid