🚀 go-pugleaf

A PPD is highly device-specific, and only someone who's ever done it before or who's willing to take the time to look at your PPD is able to help. 

Regards, 
Victor Lee.

For a colour printer, you cannot generaly suppress colour by changing the PPD. Even for b&w printers, an application is
free to send coloured text/graphics to the printer, and the device driver does not convert that to grayscale. You can
end up with pages that are partly in colour (text) and partly in b&w (raster graphics, for which the app bothered to
check if the printer supports colour and decided to send them in grayscale to reduce the amount of data).

The only chance would be if the printer itself could disable colour. But even then changing the PPD is not foolproof.
The whole PostScript code is generated on the client computer, and depends on the PPD installed there. A client may use
the colour PPD, then change the printer port to the b&w queue.

SaGS, 

I think the whole point of it is creating two separate instances of the printer: a normal healthy one, and one stripped of all indication of a colour printer or else toggled to that effect. 

Regards, 
Victor Lee.

Pleader,

Yes, I understood that. But it seems to me that the purpose of creating the 2 printer queues is to disallow some users
to use colour, and that cannot be safely acomplished by tricking the PPD. And I also mentioned that if you (a) print a
colour document (b) using a b&w PPD and (c) send the generated PostScript to a colour printer, you can easily get a
document that is not fully converted to b&w, but with some parts in colour (which again defeats the purpose of getting
b&w/ grayscale printed pages).

SaGS, 

At the risk of jumping to conclusions, I think the main idea is to save costs. Colour printouts are considerably more expensive than B&W. The presence or absence of colour values in the PostScript files is not relevant. 

Eric's printer has the "option to print B&W". Some printers are like that. Toggle a PostScript invocation properly, and voila, the printer only prints using black toner using grayscale values. Or perhaps a PostScript string is clobbered. But the idea is that the user is restricted to whatever choice Eric wants him to have. 

I think it is too early to say that this "cannot be safely accomplished by tricking the PPD". The PPD is altered. It's the driver which is tricked into seeing the printer as grayscale or activating the colour toggle. 

By the way, my real name appears at the signature block. Pleader is merely a login name. 

Regards, 
Victor Lee.

I have a similar problem to this. Students at my work are able to print to the black and white queue with a color print job. 

Is there a black and white only postscript driver. That would be excellent or otherwise a driver that allows selection of black/white or color on install and no modification without accessing the control panel. 

Any help would be greatly appreciated. 

Thanks, 
Jaymo