Re: Question on background jobs

Joachim Schmitz wrote:
Barry Margolin wrote:
In article
<71394f16-cdc8-4d97-998f-216c58ac9e19@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
bsh <brian_hiles@xxxxxxxxxxxxxx> wrote:

On Jun 24, 12:54 pm, Chad <cdal...@xxxxxxxxx> wrote:

Then how come you can't have job control in a non-interactive shell
(via a script)

It does. Investigate [in at least ksh(1)] the monitor shell option:

set -o monitor

From the ksh(1) manpage:

If the monitor option of the set command is turned on, an
interactive shell
associates a job with each pipeline. It keeps a table of current
jobs, printed
by the jobs command, and assigns them small integer numbers. When a
job is started asynchronously with &, the shell prints [a line
associating
that command with a job number].

That description says that the option affects interactive shells, his
question was about non-interactive shells.

Note that ksh and bash (and probably other shells) have a -i option
to make it interactive even if it's executing a script. So if you
really wanted to have job control enabled in a script, you could
start it with:

#!/bin/ksh -i

I've never tried this so I'm not sure how it would affect things.
I just did (see the thread about "Running a command for a limited
time". "set -m" is switching on job control for non-interactive shells
After being hinted about that switch by Bill Marcum...

#!/bin/ksh -m

Bye, Jojo


.

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