[GRASSLIST:4207] Re: mapset permission denied....

Glynn Clements glynn.clements at virgin.net
Fri Aug 2 16:14:12 EDT 2002

Allard, Yannick (EXP) wrote:

> 	I dont want the other user to write in the mapset but only browse
> throught the existing raster files and display them. All UNIX permissions
> are correctly set for the read.

One problem is that, even if you only wish to "read" maps, some files
will be written in the mapset directory. E.g., set_data creates a lock
file there, and the current region is saved there, as is the current
imagery group and subgroup, and the mapset search path.

Also, any temporary files are created in a subdirectory of the current
mapset (monitor sockets used to be created in the temporary files
directory, but have been moved to /tmp to avoid problems with long

> 	But if the application create another "temporary empty" mapset, will
> the other users will be able to browse through the other mapsets ( those
> they dont own ) and access the raster files and maybe perform calculations
> using those data ??? (the programmer's guide say it should...)

A program can read maps from any mapset in the current location. Maps
are located using the current mapset search path (see g.mapsets), but
this can be overriden by using a qualified map name; the format is
"map at mapset".

> 	And how can we create a mapset??? I don't think I've saw it in the
> programmer's guide???

The set_data program (this is the one which generates the usual
startup screen, allowing the database, location and mapset to be
selected) uses the make_mapset() function (from
src/general/init/mke_mapset.c) when creating a new mapset.

This function does two things:

1. Create the directory.
2. Copy <location>/PERMANENT/DEFAULT_WIND to <location>/<new mapset>/WIND.

That's all.

Glynn Clements <glynn.clements at virgin.net>

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