Concurrent d.rast

martijn at martijn at
Tue Jul 5 08:39:56 EDT 1994

Hi Conn,
1) Is there any reason why you shouldn't use one monitor with multiple 
2) If your <map1> and <map2> are in different regions, that might cause 
trouble. If the region is set correctly for <map1>, <map2> will display 
as a blank white map. You could try setting new regions (and erasing 
them) in your script, but I have no idea what happens to backgrounded 
`d.rast` commands if you change the region....

P. Martijn van Leusen
Institute of Prehistory, University of Amsterdam   martijn at

On Tue, 5 Jul 1994, Conn Copas wrote:

> I have a problem trying to display graphics to several monitors simultaneously.
> What I have done is started a number of monitors, and then written a script
> which contains instructions like:
> 	d.mon select=x0
> 	d.rast <map1>&
> 	d.mon select=x1
> 	d.rast <map2>&
> 	etc
> Each 'd.rast' command spawns a separate process, but these seem to interfere
> with each other, with the result that some monitors wind up blank. Questions:
> (a) Am I trying to do something which the X driver does not support? I have
> noticed that most demo scripts write to graphics monitors in a sequential
> fashion (still on release 4.0, btw)
> (b) What happens if different users, on different X terminals, all try to
> display at once - do they receive concurrent or sequential service?
> -- 
> Conn V Copas
> Information Technology Division
> Defence Science and Technology Organisation
> PO Box 1500
> Salisbury            tel: +61 (0)8 25 95349
> SA  5108             fax: +61 (0)8 25 96781
> Australia       e-mail: cvc at
> -------------------------------------------          

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