Why Unix automatically logs you out

Many Unix systems automatically close terminal sessions that have been inactive or signed on for too long. Typically, users may not change this behavior, as it is crucial to preserve resources and maintain security.

The tcsh shell also has a feature that disconnects sessions after a period of inactivity. On many systems, the default is 60 minutes, after which the message "auto-logout" appears and the shell exits. You can modify this behavior by deactivating or changing the autologout variable. To turn autologout off altogether, at the shell prompt, enter:

 unset autologout

In this state, a tcsh session will never self-terminate, though it will respond to disconnect commands from the system or user. If you want to change the length of idle time tcsh waits before issuing an autologout, at the shell prompt, enter:

 set autologout=n

Replace n with the amount of idle time, in minutes, you want tcsh to wait. To permanently unset or change the autologout variable, put these commands in your .login file (for login shells only) or .cshrc file (all shells).