Concurrent use of GRASS4.2

Conn Copas conn.copas at dsto.defence.gov.au
Wed Jul 15 21:57:37 EDT 1998


Jill Schuler <jschuler at tulip.itc.nrcs.usda.gov> writes:
 
> NRCS modified the startup script and GIS.sh script for concurrent use for
> GRASS4.13.  These changes should work for GRASS4.2 code.  
> Add a positional argument to the grass4.2 startup script
> 
> Then the same user can start many different GRASS sessions in the 
> same location/mapset or in a new location/mapset by typing:
> 
> grass4.13 sess=1, or grass4.13 sess=2,  or grass4.13 sess=4, etc.

The problem remains that multiple users, logged-in with the same user id, are 
likely to interfere with each other because of Grass's habit of writing session 
information to files instead of maintaining that information as a 
process-specific memory variable. Eg, two people working in the same 
location/mapset can potentially overwrite each other's current WIND and 
SEARCH_PATH settings. Regardless of location, they can overwrite each other's 
current MONITOR setting (which is written to $GISRC).

I do not quite see why sys admins insist on multiple users employing a common 
log-in, but the demand seems to be there. Single users running concurrent 
sessions represent less of a problem, but they still need to remember what they 
have done in each window.



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