On Friday 11 May 2007, Bill Nottingham wrote:
Why not just check the exit status of useradd? There is a specific
exit status for 'user already exists'.
Possible, but would result in quite a bit of "useradd: user foo exists" noise
on package upgrades or more complicated %pre scriptlets that filter out this
particular error message but let others through. useradd would benefit from
an option similar to groupadd's -f.