csh(1) will close when pressing CTRL-C. This is a very unwelcome behaviour because I switch between Windows and FreeBSD environment all the time and in Windows, CTRL-C is the copy command.
Here is an example of session:
banyan<on>41: csh -f
% echo oo bar
% uname -a
FreeBSD banyan.cs.ait.ac.th 10.2-RELEASE-p12 FreeBSD 10.2-RELEASE-p12 #2 r295233: Thu Feb 18 13:42:07 ICT 2016 firstname.lastname@example.org:/usr/obj/usr/src/sys/CSIM amd64
I launch a new C Shell, without loading any rc confifiguration. CTRL-C is inactive as long as I have not executed a command (shell internal command are not concerned). As soon as I have executed one command, for example uname, CTRL-C will close the shell.
I have several amd64 systems exhibiting the same behaviour (one 10.2-RELEASE-p10 is immune), while on i386, I have no problem, CTRL-C does nothing in csh(1) (except one 10.2-RELEASE-p10).
I have repeated the same behaviour on the console and in xterm.
It seems that this appeared with the latest security patches, around the new year, but it is only recently that I finally noticed the pattern.
There is thread about this problem: https://forums.freebsd.org/threads/53868/
The problem seems to depend on winbind (or similar) in nsswitch.conf to be activated.
The same problem seems to exist on 10.2-RELEASE-p14 (amd64) with /rescue/csh (independent from nsswitch.conf).
*** This bug has been marked as a duplicate of bug 208132 ***