Geografic-Information-System/general/g.findfile/g.findfile.html

<h2>DESCRIPTION</h2>

<em>g.findfile</em> is designed for Bourne shell or Python scripts
that need to search for mapset <em>elements</em>, including: raster,
vector maps, region definitions
and <em><a href="i.group.html">imagery</a></em> groups.
<p>The list of <b>element</b> names to search for is not fixed; any
subdirectory of the mapset directory is a valid <b>element</b> name.
<p>However, the user can find the list of standard GRASS <b>element</b>
names in the file <tt>$GISBASE/etc/element_list</tt>. This is the file
which <em><a href="g.remove.html">g.remove</a></em>, <em><a href="g.rename.html">g.rename</a></em>
and <em><a href="g.copy.html">g.copy</a></em> use to determine which files
need to be deleted/renamed/copied for a given entity type.

<h2>NOTES</h2>

<em>g.findfile</em> writes four lines to standard output:

<div class="code"><pre>
name='<em>file_name</em>'
mapset='<em>mapset_name</em>'
file='<em>unix_filename</em>'
fullname='<em>grass_fullname</em>'
</pre></div>

The output is <em>Bash</em> commands to set the variable
<em>name</em> to the GRASS data base file name,
<em>mapset</em> to the mapset in which the file resides,
and <em>file</em> to the full UNIX path name for the named
file. These variables may be set in the <em>Bash</em>
as follows:

<div class="code"><pre>
eval `g.findfile element=name mapset=name file=name`
</pre></div>

<h2>EXAMPLES</h2>

<h3>SHELL</h3>

<b>Raster map example:</b>

<div class="code"><pre>
eval `g.findfile element=cell file=elevation`
</pre></div>

If the specified file (here: raster map) does not exist, the variables
will be set as follows:

<div class="code"><pre>
name=
mapset=
fullname=
file=
</pre></div>

The following is a way to test for this case:
<div class="code"><pre>
if [ ! "$file" ]
then
	exit 1
fi
</pre></div>

<p>
<b>Vector map example (including error message):</b>

<div class="code"><pre>
eval `g.findfile element=vector file="$G_OPT_V_INPUT"`
if [ ! "$file" ] ; then
   g.message -e "Vector map <$G_OPT_V_INPUT> not found"
   exit 1
fi
</pre></div>

<h3>PYTHON</h3>

See <em><a href="https://grass.osgeo.org/grass80/manuals/libpython/">Python
Scripting Library</a></em> for more info.
<p>
Note: The Python tab in the <em>wxGUI</em> can be used for entering the
following code:
<p>
<div class="code"><pre>
import grass.script as gcore
    
gcore.find_file('elevation', element = 'cell')
</pre></div>

<h2>SEE ALSO</h2>

<em>
<a href="g.filename.html">g.filename</a>,
<a href="g.gisenv.html">g.gisenv</a>,
<a href="g.mapsets.html">g.mapsets</a>,
<a href="g.parser.html">g.parser</a>
</em>

<h2>AUTHOR</h2>

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