background job status update

background job status update

[Atom Smasher]

if i start a job in the background such as:
 	sleep 30 &
  i get a status report sent to stderr as expected:
 	[1] 1234
  but when the job exits, i get this to my terminal:
 	[1]  + done       sleep 30

i would expect both of those messages to be sent to stderr. why is the 
second message sent to my terminal? how can i direct it to stderr?

tested with zsh 4.3.6.

thanks...


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Re: background job status update

[Bart Schaefer]

On Mar 14,  9:18pm, Atom Smasher wrote:
} Subject: background job status update
}
} if i start a job in the background such as:
}  	sleep 30 &
}   i get a status report sent to stderr as expected:
}  	[1] 1234
}   but when the job exits, i get this to my terminal:
}  	[1]  + done       sleep 30
} 
} i would expect both of those messages to be sent to stderr.

Funny, I'd expect both to be sent to the terminal.

The problem is that spawnjob() doesn't go through printjob() to format
the output of "[1] 1234" (silly aside: as I was testing this, process
IDs on my machine passed through "12345") and instead simply writes
directly to stderr.  I think at the very least it should be using the
special shout (shell output) file pointer, which is what printjob()
does during all job control operations thereafter.

I'm not sure why it doesn't just use printjob(); probably historic from
when both of those functions were simpler.

} why is the 
} second message sent to my terminal? how can i direct it to stderr?

You can't.

All you can do is suppress it by unsetopt monitor or by starting the
background job in a subshell, or delay it by unsetopt notify.

Re: background job status update

[Peter Stephenson]

On Sat, 14 Mar 2009 10:26:18 -0700
Bart Schaefer <schaefer@brasslantern.com> wrote:
> The problem is that spawnjob() doesn't go through printjob() to format
> the output of "[1] 1234" (silly aside: as I was testing this, process
> IDs on my machine passed through "12345") and instead simply writes
> directly to stderr.  I think at the very least it should be using the
> special shout (shell output) file pointer, which is what printjob()
> does during all job control operations thereafter.

We might as well put that right.  Note that printjob() uses stdout if
it's for a command where the user has requested a status output; that
doesn't seem to apply here.

> I'm not sure why it doesn't just use printjob(); probably historic from
> when both of those functions were simpler.

printjob() doesn't currently do the right thing even if called at that
point.  There's no reason it couldn't, but I doubt if the result would
be a code saving or a clarification.

> } why is the 
> } second message sent to my terminal? how can i direct it to stderr?
> 
> You can't.

... the point being this is *interactive* job control based around a
terminal session.  It's not a general purpose mini-process-management
system.

Index: Src/jobs.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/jobs.c,v
retrieving revision 1.64
diff -u -r1.64 jobs.c
--- Src/jobs.c	31 Jul 2008 08:44:21 -0000	1.64
+++ Src/jobs.c	14 Mar 2009 18:36:05 -0000
@@ -1380,11 +1380,11 @@
 	} else if (prevjob == -1 || !(jobtab[prevjob].stat & STAT_STOPPED))
 	    prevjob = thisjob;
 	if (interact && jobbing && jobtab[thisjob].procs) {
-	    fprintf(stderr, "[%d]", thisjob);
+	    fprintf(shout, "[%d]", thisjob);
 	    for (pn = jobtab[thisjob].procs; pn; pn = pn->next)
-		fprintf(stderr, " %ld", (long) pn->pid);
-	    fprintf(stderr, "\n");
-	    fflush(stderr);
+		fprintf(shout, " %ld", (long) pn->pid);
+	    fprintf(shout, "\n");
+	    fflush(shout);
 	}
     }
     if (!hasprocs(thisjob))


-- 
Peter Stephenson <p.w.stephenson@ntlworld.com>
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