Should ``csh'' be part of the System V distribution?

karish karish at denali.stanford.edu
Mon May 16 04:44:59 AEST 1988


In article <2601 at usceast.UUCP> still at cs.scarolina.edu (Bert Still) writes:
>WHEREAS the style of csh more closely resembles the C language (hence the name
>	of the shell) than the Bourne or Korn shells, and
This is true, in a formal sense.  This feature should be useful mostly
in writing scripts.  Unfortunately, it is still painful to get the syntax
right, with the correct quotes, backslashes, etc.  And csh execution
(startup) is still slow.

>Incidentally, as far as I know, no one
>uses the Korn shell.

How many of your systems have ksh installed?

I'm trying out ksh now, after four years of using csh exclusively
(interactively).  The transition was easy.  I don't feel anywhere near
as restricted as I do when I use sh interactively.  The only thing I
miss is the '!$' construct; I suspect that there's a way to do this
under ksh, but I haven't found it yet.

The history, command line editing, and filename expansion previewing
features are superior to what csh offers, and in ways that make ksh
especially useful for naive users.  The key is that you always can see
the whole command line before you execute it.  This is much safer than
the csh history mechanism, which involves stabs in the dark using an
ed-like command set, with the added complexity of avoiding interference
with the shell's interpretation of special characters.

It is possible to do command-line editing of multi-line command
constructs.  Since ksh is a superset of sh, this makes ksh a
very powerful tool for prototyping fast, portable shell scripts.
Bourne shell scripts so produced are backwards compatible with
all existing U*ix systems; adding csh to the Sytem V package
would only help new buyers.

Unfortunately, AT&T isn't marketing ksh in a way that encourages its
adoption as a standard.  I'd like to see it bundled with System V,
instead of being an extra-cost option from the Toolchest.  The price
of  a re-distribution license is reportedly about $20,000, which is too
high, until there's a demand for the program.  The demand won't be
there until people can try the program, and we go around and around.

Some of Korn's claims for the program are a bit exaggerated.  It's
still a good piece of work, and a worthy replacement for csh.
Chuck Karish		ARPA:	karish at denali.stanford.edu
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