topic Re: Disable Control-C on Linux in Operating System - Linux

Disable Control-C on Linux

M.A. — Thu, 24 Jun 2004 03:24:56 GMT

Hi All,

I have created a user TEST. How do i disable the Control-C(to break some operation) button and it should only affect this particular user, and not everybody.

I know we can do that in HPUX, but how is it in Redhat 7.0?

Thank you.

Re: Disable Control-C on Linux

Mark Grant — Thu, 24 Jun 2004 04:19:51 GMT

You can do this in the users .profile with the following near the top

trap "" 2

Of course, you need to make sure that the .profile is read. If they log in via xdm/gdm/kdm and then run some type of terminal, you need to make sure that the terminal is started with a "-ls" to ensure the .profile is read. Anyway, however they log in, put the above in .profile and make sure th e .profile is sourced. If it a normal telnet log in, you won't need to do anything else.

Re: Disable Control-C on Linux

M.A. — Thu, 24 Jun 2004 04:28:56 GMT

Im sorry, but which .profile are you referring to? I tried to find but all i have is .bash_profile. Is this the one?

btw, the user is trying to access using normal telnet from any other server.

TQ.

Re: Disable Control-C on Linux

Mobeen_1 — Thu, 24 Jun 2004 05:45:19 GMT

Abdullah,
Mark is talking about the users profile file .profile in the users home directory.

rgds
Mobeen

Re: Disable Control-C on Linux

shetty — Thu, 24 Jun 2004 06:40:41 GMT

Hi Abdullah,
Yeah you are correct, You can find .bash_profile in /home/user_name directory.

There you have to edit as per Mark has said. I hope this will work.

Shetty.

Re: Disable Control-C on Linux

Jan Sladky — Thu, 24 Jun 2004 06:42:18 GMT

hi,
.profile should be placed in $HOME, if is not , create it.

other way how to forbid Ctrl+C is following row in .profile:

stty intr =

(all tty settings you get by stty -a)

br Jan

Re: Disable Control-C on Linux

Stuart Browne — Thu, 24 Jun 2004 18:37:45 GMT

Jan has the best idea.

CTRL-C is just the shell sending a signal. All you have to do is stop the shell, which is done through 'stty'. The 'intr' (Interrupt, SIGINT) is what you're trying to stop.

Unfortunately, Jan's post will change the CTRL-C to just the '=' key ;)

To disable it, use the following:

stty intr undef

Put this in '/etc/profile' to disable it for all users, or in the users '.bash_profile' (or '.bashrc') file for an individual user (reccomended).

Re: Disable Control-C on Linux

Muthukumar_5 — Fri, 25 Jun 2004 00:48:45 GMT

hai,

For every user contains .bash_profile file in their home directory to define it's environment variables or settings.

Else copy the root /.bash_profile file to your home directory and change the owner and file permissions.

Control-C is normally known with intr signal. We can remove that signal as

# stty -isig intr
# ^C
After that it will print that control+c value on the screen. It won't do the action.

You can use stty raw intr to do the same effect. But the prompting will be not as like normal

To know more about control+c ,use ksh man page on intr keyword

Regards,
Muthukumar.