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From: pfalstad@phoenix.Princeton.EDU (Paul Falstad)
Newsgroups: comp.unix.shell
Subject: Re: Problems with Job Control in csh
Message-ID: <8075@idunno.Princeton.EDU>
Date: 9 Apr 91 22:44:32 GMT
References: <1991Apr9.133344.1733@mintaka.lcs.mit.edu>
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streeter@theory.lcs.mit.edu (Kenneth B Streeter) wrote:
>I'm having problems with trying to do job control in a csh script.  I
>want to be able to commence a background job (I'm using the &
>metacharacter), use it for some request-handling, and then later kill
>the backgrounded job.
>    xterm -e "<my-executable>" &
>    # <processing deleted>
>    kill %1

You can't refer to process with the "%<number>" construct in
noninteractive shells in csh; you can only do it when job control is in
effect.  Really, this should not require job control to be in effect;
for example, this script will work fine in zsh, and also in itcsh, I
believe.  But if you're using an sh-derived shell (sh,ksh,bash,...) this
will work fine:

xterm -e "foobar" &
# ...
kill -9 $!

I think the only way to do this in csh is to do something like this:

xterm -e "foobar" &
# ...
kill -9 -$$
# end of script

where the "kill" kills off the shell and the xterm by killing the
whole process group.  You're better off not to write the script in csh IMHO.

--
Paul Falstad, pfalstad@phoenix.princeton.edu | 10 PRINT "PRINCETON CS"
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