As you will see in the vast majority of comments by sysadmins, csh is to be avoided at all costs. Die-hard programmers like it because it's the only shell they learned, but unless tghe programmer has their own private workstation and doesn't need any help, switch your users to the POSIX shell. Note that ksh is also a POSIX shell but with a few limitations. BASH is also a POSIX shell but not supplied with the Core OS.
There are so many conceptual differences between POSIX shells and csh that it is quite difficult to contrast them. In a POSIX shell, you can find out exactly what a command (like export) is by typing: whence -v export. The POSIX shell will tell you that it is a built-in, or part of the shell.
So if you have to answer all these csh newbie questions, you can either learn csh in depth, or switch your users. Note also that the value for the DISPLAY value may have been set automatically, possibly by parsing the IP or name (fh-cae-rxkwrk.matsci.com) from the who -muR command. The problem is that the user may have used telnet to 'tunnel around' through several servers until arriving on the current one and who -muR reports only the adjacent machine, not the originator of the request. Make sure the DISPLAY variable matches the machine the user is really on.
Bill Hassell, sysadmin
