[GRASSLIST:5992] RE: Concurrent use of GRASS

Thu Mar 3 16:34:34 EST 2005

Hello Jose,

This worked for me (although I did not process any data that way, the 
concurrent use works):
go in the directory parent directory of your GISbase, for example:
home/jose/grassdata/..

in this directory, if you type
$ ls -attr
you should see a .grassrc53 and a .gislock53 file

well, if you start grass in a first terminal, open a second one in witch you 
remove these two files
rm -f .grassrc53; rm -f .gislock53
then you should be able to start a second grass environment (when you run 
grass, specify the environment, such as $ grass53 
/home/jose/grassdata2/location2/mapset2)

the job of .grassrc53 is to give the gis base, location and mapset location 
on the hard drive
the job of the .gislock53 file is .. well guess what!

As I said earlier, it worked for me but I did not try to process data that 
way; I would recommend to use different gisbases. As well, I am sure that 
the people that designed grass blocked concurrence use for a specific 
reason, which I do not know (I would be happy to find out, though!)

good luck !!!
eric pante

<html><div><DIV align=left>
<DIV align=left>Eric Pante</DIV>
<DIV align=left><FONT size=2>Graduate Student in Marine Biology</FONT></DIV>
<DIV align=left><FONT size=2>Grice Marine Laboratory</FONT></DIV>
<DIV align=left><FONT size=2>205 Fort Johnson, Charleston SC 
29412</FONT></DIV>
<DIV>&nbsp;</DIV>
<DIV align=center><EM>On ne force pas la curiosité, on l'éveille.</EM></DIV>
<DIV align=center>Daniel Pennac</DIV>
<DIV>
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&gt;From: Jose Luis Gomez-Dans &lt;jgomezdans at yahoo.co.uk&gt;
&gt;To: GRASSLIST at baylor.edu
&gt;Subject: [GRASSLIST:5984] Concurrent use of GRASS
&gt;Date: Thu, 3 Mar 2005 16:04:25 +0000
&gt;
&gt;Hi!
&gt;I have a dual CPU machine, and I would like to run several GRASS
&gt;programs in parallel. I found that since I need to change regions, I
&gt;end up having race conditions, and endless grief. I would rather just
&gt;use two different GRASS sessions to do things (maybe with a different
&gt;location). However, GRASS complains that
&gt;${USER} is currently running GRASS 5.4.0. Concurrent use not allowed.
&gt;
&gt;I can easily get over this by running GRASS on two different machines,
&gt;but I'd like to use my 2nd CPU for GRASS programs!
&gt;
&gt;Choose as many as you like:
&gt;a. Did I do something stupid?
&gt;b. Did I misread the manual?
&gt;c. Did I err? (Groo the Wanderer)
&gt;
&gt;thanks!
&gt;Jose
&gt;--
&gt;Jose L Gomez-Dans, Research Assistant
&gt;Bristol Glaciology Centre, Geographical Sciences/CPOM
&gt;University of Bristol, Bristol, UK
&gt;