g.ask(1)

NAME
g.ask - Prompts the user for the names of GRASS data base files.

KEYWORDS
general

SYNOPSIS
g.ask
g.ask help
g.ask type=string [prompt="string"] element=string [desc="string"] unixfile=string

  Parameters:

type=string
    The type of query Options: old,new,any,mapset

prompt=
    The prompt to be displayed to the user

element=string
    The database element to be queried

desc=
    A short description of the database element

unixfile=string
    The name of a unix file to store the user's response

DESCRIPTION
g.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 location. After g.ask is invoked with needed parameters, it will query the user for a file name of the specified type and element. After the user responds to this query, the program will write four lines to the UNIX output file specified by unixfile.

OUTPUT
Upon receiving the user's response to its request for a file name, g.ask writes four lines to the specified unixfile; this output file is placed in the user's current working directory, unless otherwise specified, and contains the following lines:
name='some_name'
mapset='some_mapset'
fullname='some_fullname'
file='some_fullpath'

The output is /bin/sh commands to set the variable name to the file name specified by the user (of the element and type requested by g.ask), mapset to the GRASS mapset in which this file resides (or will be created), fullname is the name with the mapset embedded in it, and file to the full UNIX path name identifying this file. These variables may be set in the /bin/sh as follows: . unixfile

The . is a shell command which means read the unixfile and execute the commands found there. It is NOT part of the unixfile name and MUST be followed by a space.

NOTES
The user may choose to simply hit the return key and not enter a file name. If this happens the variables will be set as follows:
name=
mapset=
fullname=
file=

The following is a way to test for this case:
if [ ! "$file" ]
then
    exit
fi

SEE ALSO
d.ask, g.filename, g.findfile, g.gisenv, g.parser

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

Last changed: $Date: 2005/12/07 13:31:15 $

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