To restrict a user to only one active login, change that user's shell to some "wrapper" which implements one-at-a-time locking. That will give the added benefit of preventing said user from forking shells via 'xterm'.
(And, sure, they could change the shell, but they'd need to know HOW, and how far do you want to go?) -- R; ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
