### GRASS GIS Tips and Tricks

[more to be added]

- Error messages: To avoid sending error messages by email, generate an empty file called GIS_ERROR_LOG in your home directory:
cd $HOME
touch GIS_ERROR_LOG
Then set the environment variable GRASS_STDERR to 1 (or any other value), now errors will be printed into $HOME/GIS_ERROR_LOG:
export GRASS_STDERR=1
or, depending on your shell
setenv GRASS_STDERR 1
- Save GRASS commands: To store the commands of a GRASS session, use the UN*X command "script".
- To get personal BASH shell definitions (aliases, color listing option, ...) into GRASS, store them in `~/.grass.bashrc`
- Monitor and print-to-file driver information
- GRASS 5 Environment variables
- Piping commands to a GRASS module:
  For usage in a script (will generate two maps):

r.mapcalc << EOF
foo = 3.14159
baz = sqrt(foo)
EOF

For usage from a text file:

cat > /tmp/textfile.asc <<EOF
foo = 3.14159
baz = sqrt(foo)
EOF

r.mapcalc < /tmp/textfile.asc

- Data Import into GRASS
- Data Export from GRASS

### Other Commands

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