promislo@qucis.UUCP (Eric Promislow) (04/01/86)
I think the latest debate on problems with struggling with the vagaries of C-shell programming points out a couple of problems many people find: 1.) First, the Berekely people seem to have a propensity towards documenting everything once. Exactly once. As Greg mentioned, I recall reading somewhere that the shell won't do a history substitution on an exclamation point if it is followed by white space or a newline. I don't know where I read it (probably in the csh manual), but I know it wasn't mentioned in the test (1) page. This is the sort of thing that causes people to dump on Unix (and C) for overloading operators. 2.) Those beginners with the fairly common misfortune of not having a guru around have a fairly vast choice of books to look at on getting started, all assuming that the reader is using the Bourne shell (okay, this holds at least for all the books I've looked at). I've used about six different Unix systems, III, V, and 4.2, and nobody used the Bourne shell on it. I'm beginning to suspect the authors skip the C-shell (with perhaps a perfunctory aside towards mentioning the '%' prompt) exactly because of the sort of complications Messrs. Dunn and Woods pointed out. If anyone out there has compiled a short but complete guide to effective C-shell programming and usage, we sure could use a copy around here. As for my advice, I learned the history mechanism largely by trial and error, appreciate the escape-key completion (documented nowhere, as far as I can tell) and job-control features, and do all my shell programming with the Bourne shell. I don't see any reason to write scripts in the C-shell, except for the aforementioned exercising of masochistic tendencies. Eric Promislow, Queen's University, Kingston, Ontario ( ...utcsri!ihnp4!promislo )
karl@cbrma.UUCP (Karl Kleinpaste) (04/02/86)
In article <132@qucis.UUCP> promislo@qucis.UUCP (Eric Promislow) writes: > As for my advice, I learned the history mechanism largely by >trial and error, appreciate the escape-key completion (documented >nowhere, as far as I can tell) It's not documented because it's not part of the standard csh. There are a several versions of tenex completion and line-editing front-ends for csh out there. Ken Greer at HP sent out the first one in Oct 1983. Paul Placeway sent out a version of a line editor front end about 2 years ago. I have another which I wrote because I don't like Paul's. I'd distribute it, but I've had problems (political, not technical) with doing so. The distributed front-ends of this type for csh have always been distributed with manual pages of some sort. If you haven't got such manual pages around, complain to your sysadmin about it. -- Karl Kleinpaste
jpn@teddy.UUCP (04/03/86)
In article <132@qucis.UUCP> promislo@qucis.UUCP (Eric Promislow) writes: > 1.) First, the Berekely people seem to have a propensity towards >documenting everything once. Exactly once. As Greg mentioned, I recall >reading somewhere that the shell won't do a history substitution on an >exclamation point if it is followed by white space or a newline. I >don't know where I read it (probably in the csh manual), but I know it >wasn't mentioned in the test (1) page. This is the sort of thing that >causes people to dump on Unix (and C) for overloading operators. Why SHOULD it be documented in "test(1)"?!? Conditionals in csh do NOT USE "test(1)". In fact, the syntax of csh conditionals is different than test(1). You must be thinking about sh scripts! However, it IS documented under "csh", where it ought to be. What is unfortunate is the overloading of '!' as the not operator and the history selector. I believe this is a historical problem, since history was added late in csh'es development. Anyway, it probably ought to be pointed out in a warning note near the description of conditional expressions. Thank GOD the berkeley people only document ONCE! I HATE the VMS manuals! A better documentation cross reference would be useful, though. > If anyone out there has compiled a short but complete guide to >effective C-shell programming and usage, we sure could use a copy >around here. I'm sure there are books. I never felt the need for them. See below. > As for my advice, I learned the history mechanism largely by >trial and error, appreciate the escape-key completion (documented >nowhere, as far as I can tell) and job-control features, and do all my >shell programming with the Bourne shell. Well, escape-key completion is NOT part of the standard C-shell, so I suspect that you are running a bastardized version of csh. Why not ask your system guru (the one who installed the bastardized version!?) Also, don't you have a copy of "An Introduction to the C shell" by William Joy? It is an online document in /usr/doc/csh on all Berkeley systems, and it is in our printed manuals too! I felt that it was an adequate introduction to all the csh features. An excerpt from the introduction: UNIX users who have read a general introduction to the system will find a valuable basic explanation of the shell here. Simple terminal interaction with _c_s_h is possible after reading just the first section of this document. The second section describes the shells capabilities which you can explore after you have begun to become acquainted with the shell. Later sections introduce features which are use- ful, but not necessary for all users of the shell. Back matter includes an appendix listing special char- acters of the shell and a glossary of terms and commands introduced in this manual.
ken@rochester.ARPA (Ipse dixit) (04/03/86)
In article <132@qucis.UUCP> promislo@qucis.UUCP (Eric Promislow) writes: > 1.) First, the Berekely people seem to have a propensity towards >documenting everything once. Exactly once. More like at most once. And in places like the source. Just whining. Forget it. Ken -- UUCP: ..!{allegra,decvax,seismo}!rochester!ken ARPA: ken@rochester.arpa Snail: CS Dept., U. of Roch., NY 14627. Voice: Ken!
dricej@drilex.UUCP (Craig Jackson) (04/06/86)
Fortunately for everybody, a csh book is now available. It's called
"The Unix C Shell Field Guide", by Gail Anderson and Paul Anderson, published
by Prentice-Hall. It appears to be a fairly good coverage of the subject.
--
Craig
UUCP: {harvard,linus}!axiom!drilex!dricej
BIX: cjacksonwoods@hao.UUCP (Greg Woods) (04/07/86)
> I don't see any reason > to write scripts in the C-shell, except for the aforementioned > exercising of masochistic tendencies. I do. csh(1) has a lot of built-in execution, whereas sh(1) has to fork a separate process (test(1)) for every bloody "if" test. Bourne shell scripts, on our poor overloaded VAX 750, are slooooooow. --Greg
ed@mtxinu.UUCP (Ed Gould) (04/09/86)
>If anyone out there has compiled a short but complete guide to >effective C-shell programming and usage, we sure could use a copy >around here. _The_Unix_C_Shell_Field_Guide_ by Gail Anderson and Paul Anderson has just been publshed by Prentice-Hall: 400pp, paper, $23.95. Write to Prentice-Hall, Inc. Book Distributioni Center Route 59 at Brook Hill Drive West Nyack, NY 10995 or check a good bookstore. -- Ed Gould mt Xinu, 2910 Seventh St., Berkeley, CA 94710 USA {ucbvax,decvax}!mtxinu!ed +1 415 644 0146 "A man of quality is not threatened by a woman of equality."
henry@utzoo.UUCP (Henry Spencer) (04/10/86)
> ...csh(1) has a lot of built-in execution, whereas sh(1) has to > fork a separate process (test(1)) for every bloody "if" test. Bourne > shell scripts, on our poor overloaded VAX 750, are slooooooow. Have you considered getting a modern Bourne shell (as opposed to the ancient one distributed with 4.2)? This was fixed long ago. -- Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,decvax,pyramid}!utzoo!henry
philip@axis.UUCP (Philip Peake) (04/10/86)
In article <2045@hao.UUCP> woods@hao.UUCP writes: >> I don't see any reason >> to write scripts in the C-shell, except for the aforementioned >> exercising of masochistic tendencies. > > I do. csh(1) has a lot of built-in execution, whereas sh(1) has to >fork a separate process (test(1)) for every bloody "if" test. Bourne >shell scripts, on our poor overloaded VAX 750, are slooooooow. > Try using a System 5.2 version of sh, it may just make your csh seem like a snail! ------------------------------------------------------------------------------- UUCP: {mcvax,vmucnam,inria}!axis!philip -- ------------------------------------------------------------------------------- UUCP: {mcvax,vmucnam,inria}!axis!philip
jkh@ucbopal.berkeley.edu (Jordan K. Hubbard) (04/11/86)
>It's not documented because it's not part of the standard csh. There >are a several versions of tenex completion and line-editing front-ends >for csh out there. Ken Greer at HP sent out the first one in Oct >1983. Paul Placeway sent out a version of a line editor front end >about 2 years ago. I have another which I wrote because I don't like >Paul's. I'd distribute it, but I've had problems (political, not >technical) with doing so. This is part of the 4.3 BSD csh.. It's invoked by setting the shell variable 'filec' to something.. The original (Greer) tcsh also used to do terminal sanity checking when a program exited and set it back to something normal if it seemed braindamaged in some way. This was useful, but as Mike Meyer just pointed out: What happened when you ran stty? Did it set you back afterward? I didn't know the answer to that question (it was probably kludged), but we're pretty sure that the 4.3 csh doesn't do that for you.. So the REAL answer is that 4.3 csh doesn't do EVERYTHING tcsh did..