Rejecting Control C from Users

[David Land]

Is there a way to prevent a user from being able to perform a ^C (Control C) to get to a command line?

I am in the process of trying to lock down some user accounts from being able to ^C out of a menu I have created.

[Pete Randall · Accepted solution]

You can do it like /etc/profile does:

trap "" 1 2 3 # ignore HUP, INT, QUIT now.


Pete

[Tony Scully_2]

Or trap the ctrlC and do an exit, so it drops them right out.

[Bill Hassell]

Completely ignoring all the signals (especially signal 1, called SIGHUP) can leave processes hanging. It is best to detect a hangup or a CTRL-C (and others) and take an action, usually by exiting:

trap "exit" 1 2 3 15

The trap statement says that CTRL-C or a broken connection, etc, will simply exit and if your menu script is the user's login shell, they will be logged out. The trap technique is used in HP's standard /etc/profile.

[David Land]

That has helped me out. Thanks everyone. Thanks Bill, I will change the trap statement to reflect the 'exit' command.