|-s||Use shell syntax (for "eval")|
|-n||Do not use shell syntax|
|--verbose||Verbose module output|
|--quiet||Quiet module output|
get=VARIABLE GRASS variable to get set=VARIABLE=value GRASS variable to set store=string Where GRASS variable is stored
When a user runs GRASS, certain variables are set specifying the GRASS data base, location, mapset, peripheral device drivers, etc., being used in the current GRASS session. These variable name settings are recognized as long as the user is running a GRASS session.
No prompts are given to the user when running g.gisenv. If run without arguments, g.gisenv lists all of the users current GRASS variable settings. Results are sent to standard output, and may look like this:
In this example, the full path name of the users current location (i.e., $LOCATION_NAME) is /opt/grassdata/spearfish, and the full path name of the users current mapset (i.e., $MAPSET) is /opt/grassdata/spearfish/PERMANENT.
If the user specifies a variable_name on the command line (e.g., g.gisenv MAPSET), only the value for that particular GRASS variable is output to standard output. Possible variable names depend on the users system, see variables list for details.
While other variables may be associated with each GRASS session (e.g., GRASS_GUI, GIS_LOCK, and other variables), those stated below are essential.
Each "mapset" stores GRASS data base elements (i.e., the directories in which GRASS data files are stored). Any maps created or modified by the user in the current GRASS session will be stored here. The $MAPSET directory PERMANENT is generally reserved for the set of maps that form the base set for all users working under each $LOCATION_NAME.
GISDBASE The $GISDBASE is a directory in which all users GRASS data are stored. Within the $GISDBASE, data are segregated into subdirectories (called "locations") based on the map coordinate system used and the geographic extent of the data. Each location" directory itself contains subdirectories called mapsets"; each "mapset" stores "data base elements" - the directories (e.g., the cell, cellhd, vector, etc., directories) in which GRASS data files are actually stored. LOCATION_NAME The user must choose to work with the data under a single GRASS location within any given GRASS session; this location is then called the current GRASS location, and is specified by the variable $LOCATION_NAME. The $LOCATION_NAME is the GRASS data base location whose data will be affected by any GRASS commands issued during the users current GRASS session, and is a subdirectory of the current $GISDBASE. Each "location" directory can contain multiple "mapset" directories (including the special mapset PERMANENT). Maps stored under the same GRASS $LOCATION_NAME (and/or within the same MAPSET) must use the same coordinate system and typically fall within the boundaries of the same geographic region (aka, "location"). MAPSET Each "mapset" contains a set of maps relevant to the $LOCATION_NAME directory in which it appears. Each $LOCATION_NAME can contain multiple mapsets. (Mapsets which fall under the same $LOCATION_NAME all contain data geographically relevant to the $LOCATION_NAME, and all store data in the same map coordinate system. Frequently, maps are placed into different mapsets to distinguish file ownership - e.g., each user might have his own mapset, storing any maps that he has created and/or are relevant to his work.) During each GRASS session, the user must choose one mapset to be the current mapset; the current mapset setting is given by $MAPSET, and is a subdirectory of $LOCATION_NAME. During a single GRASS session, the user can use available data in any of the mapsets stored under the current $LOCATION_NAME directory that are in the users mapset search path and accessible by the user. However, within a single GRASS session, the user only has write access to data stored under the current mapset (specified by the variable $MAPSET).
Once within a GRASS session, GRASS users have access only to the data under a single GRASS data base directory (the current GRASS data base, specified by the variable $GISDBASE), and to a single GRASS location directory (the current location, specified by the variable $LOCATION_NAME). Within a single session, the user may only modify the data in the current mapset (specified by the variable $MAPSET), but may use data available under other mapsets under the same $LOCATION_NAME.
All of these names must be legal names on the users current system.
The output from g.gisenv when invoked without arguments is directly usable by Bash. The following command will cast each variable into the UNIX environment:
This works only for Bash. The format of the output is not compatible with other UNIX shells.
To print debugging messages, the variable DEBUG must be set to level equal or greater than 0:0 - silence 1 - message is printed once or few times per module 3 - each row (raster) or line (vector) 5 - each cell (raster) or point (vector) To disable debugging messages, DEBUG must be set back to 0:
Levels: (recommended levels)
g.access, g.filename, g.findfile, g.mapsets
See also variables list
Michael Shapiro, U.S.Army Construction Engineering Research Laboratory
Last changed: $Date: 2011-11-08 03:29:50 -0800 (Tue, 08 Nov 2011) $
� 2003-2015 GRASS Development Team
|GRASS 6.4.5||G.GISENV (1)|