UNIX for Dummies Questions & Answers

well.. when does the .profile come into picture?

.profile doesn't come into it at all.
According the the man page I have, csh does
not read .profile...

"An instance of csh begins by executing commands from the file /etc/csh.cshrc and, if this is a login shell, /etc/csh.login. It
then executes commands from .cshrc in the home directory of the invoker, and, if this is a login shell, the file .login in the
same location. It is typical for users on crt's to put the command ``stty crt'' in their .login file, and to also invoke tset(1)
there."

...and I do believe this is the case (at least
it was the last time I used csh about 7 years
ago) with your csh as well. You can check the
man page on your system to be sure. The only files
it loads up at start up are listed above.

well, i was in a necessity that i wanted to register the login. in the sense.. i wanted to set a variable when i first login to my system. is that possible?

Yes... you can set variables in .login and/or
.cshrc in your home directory since both of these
files will be loaded up on login.

eventhough i have a little idea about .login file.. i could not find one in my system. isn't it a necessary one?

if not necessary.. would it be considered if i create a new one in my home folder?

Not having a .login file is no problem.
Adding one is also no problem. It's really
up to you where you want to place environment
variable settings (.login or .cshrc) as csh
will automatically any or both of those upon
login.