help with c-shell input

[John J Boland]

i'm having a problem reading keyboard input into a c-shell.
i need to allow a user (c-shell) to select an environment at login.
i can do it no problem in bourne or korn shell. however, i can't change
the login shell!  as part of the login process, a bunch of variables get set that
control later steps in the login process.  i am loathe make major changes
in this process.  i'd like to prompt the user to select the desired 
environment and set the appropriate variables.
right now, i'm stuck trying to read from the keyboard!
using, bourne or korn, i'd just use 'read variable'. however, when i
try the same line in c-shell, i get "undefined variable"!
any ideas how to get the user to enter their selection?
tia....