SPECX can read data from data directories that are distinct from your working directory. This leads to directories that are far less cluttered than would otherwise be the case. SPECX does this by using the DATADIR environment variable. When a read-gsd-data or read-gsd-raster command is issued SPECX searches for the GSD file in the current directory and, if the file can not be found, then in the directory specified by DATADIR.
For example, if you stored your data in /data/jcmtrun then you would issue the following command before starting SPECX:
% setenv DATADIR /data/jcmtrun
Now when SPECX is started, the directory /data/jcmtrun will be used as
a GSD data directory. You are then ready to start up SPECX.
Specx Cookbook