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4.20 GMT environment parameters

GMT relies on several environment parameters, in particular to find data files and program settings.

$GMT_SHAREDIR
points to the GMT share directory where all run-time support files such as coastlines, custom symbols, PostScript macros, color tables, and much more reside. If this parameter is not set it defaults to the share sub-directory selected during the GMT install process (e.g., your answer to question C.9 on the web install form). If no selection was made the ultimate default is the share directory under the GMT installation directory.
$GMT_DATADIR
points to one or more directory where large and/or widely used data files can be placed. All GMT programs look in this directories when a file is specified on the command line and it is not present in the current directory. This allows maintainers to consolidate large data files and to simplify scripting that use these files since the absolute path need not be specified. Separate multiple directories with colons; under Windows you use semi-colons.
$GMT_USERDIR
points to a directory where the user may place custom configuration files (e.g., an alternate coastline.conf file, preferred default settings in .gmtdefaults4, custom symbols and color palettes, and shorthands for gridfile extensions via .gmt_io). Users may also place their own data files in this directory as GMT programs will search for files given on the command line in both $GMT_DATADIR and $GMT_USERDIR.
$GMT_TMPDIR
is where GMT will write its state parameters via the three files .gmtcommands4, .gmtdefaults4 and .gmt_bb_info. If not set then these files are written to the current directory. See Appendix P for more on the use of $GMT_TMPDIR.


next up previous contents index
Next: 5. GMT Coordinate Transformations Up: 4. General features Previous: 4.19 The NaN data   Contents   Index
Paul Wessel 2010-01-14