Alternate Shells

[rml at hpfcla.UUCP]

> >A quickie: 4.2BSD chsh does not allow the user to specify alternative
> >shells - only "sh" and "csh" are permitted. Why is this? It seems
> >ironically inappropriate in UNIX, where the shell is ``an ordinary,
> >swappable user program'' and ``user-selectable system interfaces [...]
> >become essentially trivial to implement'' [Ritchie & Thompson CACM 1974].
>
> I think you can see it more as a site policy rather than a restriction
> imposed by UNIX. Go bug your SA if you have a good argument.

I agree, that it should a matter of site policy.  Some system
administrators like the idea that the Bourne shell executes commands
from /etc/profile every time a user logs in, so they can have some
control of what the user sees or does at that time (like /etc/motd).
There were thus administrators who didn't like csh as a login shell (and
forced their users to use sh and exec a link to csh named -csh from
.profile).  For this reason HP modified csh to read commands from a file
/etc/csh.login prior to ~/.login.  Having chsh read a list of allowable
files from a file sounds like a good solution (though I'm not sure I'd
agree that the file belongs in /lib).

			Bob Lenk
			{hplabs, ihnp4}!hpfcla!rml