How does one set access to mapsets

[Susan Stitt]

Jason,

What do you mean by "access"?  The owner is the only one who 
can enter grass using that mapset to write into.  Everyone else
gains read "access" using the g.mapsets command.  They must 
enter grass using a different mapset to write into.  A common
method is to use login names as mapset names.  The PERMANENT
mapset is often owned by grass, and is usually used to contain
only the very final products which can then be used to derive
other intermediate files.  

You should be able to "see" any vector, raster, or site file
in someone elses mapset by including their mapset name in 
your mapset search path (via g.mapsets).  If you have included 
that mapset name, when you g.list rast, the raster files in all 
the mapsets in your search path should be available to you to 
read.  Whenever you write a file, it will be written into your 
mapset (the one you entered the name of when you started grass).  

This is a security feature that has been in grass since its 
beginning, allowing you to read any data files, but allowing
you to remove, write-over, modify, add-to only your own files.
It is oblivious to UNIX file permissions, you can open the 
files to the world via UNIX permissions, and grass will still
not let you write into a mapset you don't own.

I hope this provides your answer. 

Susan Stitt
National Biological Service
Technology Transfer Center
sstitt at its.nbs.gov
(303)202-4234 

  >From grass-lists-owner at moon.cecer.army.mil Thu Jan 25 08:23:23 1996
  >Return-Path: <grass-lists-owner at moon.cecer.army.mil>
  >Date: Thu, 25 Jan 1996 09:18:04 -0500 (EST)
  >From: Jason Frederick <jfrederi at lunar.nena.org>
  >Sender: grass-lists-owner at moon.cecer.army.mil
  >Reply-To: grassu-list at moon.cecer.army.mil
  >To: grassu-list at max.cecer.army.mil
  >Cc: grassu-list at max.cecer.army.mil
  >Subject: Re: How does one set access to mapsets
  >Mime-Version: 1.0
  >Content-Type  >:   >TEXT/PLAIN  >;   >charset=US-ASCII  >
  >
  >Ok, That's how I thought it should work, but even after giving everyone 
  >access to a mapset, noone can access the mapset.
  >
  >On Wed, 24 Jan 1996, Malcolm Williamson wrote:
  >
  >> On Wed, 24 Jan 1996, Jason Frederick wrote:
  >> 
  >> > I've tried to set group access to a mapset in grass4.1 by using g.access
 
  >> > and by changing the permissions of the files, but nothing seems to work.
  >> > Does anyone have any idea about what I'm doing wrong?
  >> > 
  >> Jason,
  >> g.access controls _read_ permission only for mapsets. You must be the 
  >> owner of the mapset to create or modify data layers within the mapset. 
  >> Normally you use g.mapsets to select which other mapsets, in the same 
  >> location as yours, you are interested in accessing on a read-only basis. 
  >> You can still use any of these data layers for production of other raster 
  >> or vector data layers in your _current_ mapset. I hope this makes some 
  >> kind of sense... ;^)
  >>    -Malcolm Williamson
  >> --
  >> Malcolm D. Williamson - GIS Specialist           E-mail: malcolm at cast.uark
.edu
  >> Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
  >> Ozark Rm. 12                                        Fax: (501) 575-5218 
  >> University of Arkansas              
  >> Fayetteville, AR 72701
  >> 
  >