NAME

       d.ask  - Prompts the user to select a GRASS data base file from among files displayed in a
       menu on the graphics monitor.

KEYWORDS

       display, map management

SYNOPSIS

       d.ask
       d.ask help
       d.ask element=name,description  [prompt=message]   [--verbose]  [--quiet]

   Parameters:
       element=name,description
           Database element, one word description

       prompt=message
           Short user prompt message

DESCRIPTION

       d.ask is designed for shell scripts that need to prompt the user for the name  of  a  data
       base  file  in  the  user's current GRASS mapset search path.  After d.ask is invoked with
       needed parameters, the mouse becomes active and a menu containing files of  the  specified
       element  type  is  displayed  on the user's graphics monitor.  The user is prompted by the
       prompt "message" to select one of the listed file names with the mouse. Specifically,  the
       query that appears to the user takes the form:

        Double click on the prompt "message"
        Double click here to cancel

        (A  list  of  files  of the specified element type from each of the mapsets listed in the
       user's mapset search path is also displayed.)

       After the user responds, the mouse is deactivated and the displayed menu  is  erased  from
       the  screen (leaving any underlying materials on display intact).  Three lines are written
       to standard output (the user's terminal screen):

       name=file_name
       mapset=mapset_name
       fullname=file_name@mapset_name

   Parameters:
       element=name,description
              Name of a GRASS data base element, followed  by  a  one  word  description  of  the
              element.  GRASS  data base elements are mapset subdirectories; these include: bdlg,
              cats, cell, cell_misc, cellhd, colr,  colr2,  dig,  dig_ascii,  dig_att,  dig_cats,
              dig_plus,  dlg,  group,  hist,  icons,  noise, paint, site_lists, and windows.  The
              description will be used to display an error message to the screen if no  files  of
              the  named  element  type  exist  in  the  user's  mapset  search path.  The prompt
              "message" will appear in the pop-up menu displayed on the user's graphics  monitor.
              The  files  listed  in the menu will be of the specified element type, and exist in
              mapsets listed in the user's current mapset search path.

       prompt=
              A brief message with which the user will be prompted.   If  this  message  contains
              more  than one word, it should be enclosed within double quotes ("").  It is a non-
              selectable message displayed in the menu bar of a pop-up menu.  Selectable items in
              the  displayed  menu  include  a  cancel  option and any of the files in the mapset
              subdirectory name in the user's mapset search path.

EXAMPLE

       Given the following input,

       d.ask element=cell,raster prompt="raster map layer to be used"

       d.ask will prompt the user to select a raster (cell) file from among those listed  in  the
       "cell"  directories of the mapsets listed in his current mapset search path. A pop-up menu
       will be displayed on the user's graphics monitor, containing the prompt:

        Double click on the raster map layer to be used
        Double click here to cancel

OUTPUT

       If the user selects a file name from the displayed  menu,  d.ask  writes  three  lines  to
       standard output:

        name=file_name
        mapset=mapset_name
        fullname=file_name@mapset_name

       The  output  is  in the form of /bin/sh commands to set the variable name to the file name
       specified by the user (of the element type requested by d.ask), mapset to the GRASS mapset
       in which this file resides, and fullname to the name of the file and its mapset.

       If  the  user  elects  not  to select a file but instead chooses the "Double click here to
       cancel" option, the mouse will be deactivated and no variable assignments will be returned
       to standard output.

       If  no  files  of the specified element type are found in the user's current mapset search
       path, the mouse is activated and the following message is displayed on the user's graphics
       monitor:

        No element description files found
        Click here to continue

NOTES

       Parameter values (the element name and description, and prompt message) cannot be supplied
       to d.ask interactively; they must be supplied on the command line or from a file.

SEE ALSO

        d.menu,
       g.ask,
       g.filename,
       g.findfile,
       g.gisenv,
       g.mapsets

BUGS

       This program calls other GRASS programs  which  may  generate  confusing  error  messages.
       Example: an error message from the program d.menu will appear if a nonexistent map element
       is chosen.

AUTHOR

       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory

       Last changed: $Date: 2011-11-08 03:29:50 -0800 (Tue, 08 Nov 2011) $

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       © 2003-2013 GRASS Development Team