[comp.unix.internals] LPD with multiple queues to one device

dave@sam.cs.olemiss.edu (11/01/90)

We have installed a Postscript card in one of our LaserJet II's and
wish to set up LPD to handle Postscript and HP style files.  The key
is the printer defaults to Postscript and postscript output is easy,
but HP output must switch the mode before printer (and maybe
afterwards). Having two queues pointing to the same device will not
work (I dont think) because output may be mixed since each daemon does
not know of the other one.

Has anyone attempted such a setup?  I assume so since this setup seems
to be evermore popular.  If so, how is it done?

This is the opposite problem from the one PLP solves: That is,
multiple printers on one queue.

Thanks for any information.

dave

ooms@delgeo.UUCP (Frank Ooms) (11/01/90)

In article <24906@adm.BRL.MIL> dave@sam.cs.olemiss.edu writes:
>
> [stuff deleted]
>
>Having two queues pointing to the same device will not
>work (I dont think) because output may be mixed since each daemon does
>not know of the other one.
>

we do this with bsd lpd(8) using two (or more queues) to the same
device. The output of each printjob will come out seperately, since
the open(2) on the print/plotter device prevents other programs from
sending data to that device.

We found that is not unwise to have only one queue started, but this
because we have to operate some switch before the second queue should
run.

Now, I heard that it is possible to have two spooling directories for
one queue. This enables the submission of priority jobs to the queue
without having to go through the queue shuffle of topq for every job.

has anyone ever hacked lpr/lpd to do this?




-- 
	/*	    Frank Ooms,   +31 15-621554			*
	 *	      ooms%delgeo@nluug.nl			*
 	 *		ooms@delgeo.uucp			*
 	 *	    ..!mcsun!hp4nl!delgeo!ooms			*/