## Environment variables

The following environment variables affect behaviour:
ARGYLL_NOT_INTERACTIVE
Normally Argylls tools expect that they are directly interacting with a user, and use a couple of techniques for communicating with them through the command line. One is to output progress information by re-writing the same display line by using a Carriage Return rather than a Line Feed at the end of each line. Another is to allow a single key stroke to trigger an action or interrupt operations.
If the ARGYLL_NOT_INTERACTIVE environment variable is set, then:
A Line Feed will be added to the end of each progress line.
Any time it would wait for a single keystroke input, it will instead wait for and read the next character from stdin.
To facilitate flushing stdin, any return or line feed characters will be ignored, so a character other than return or line feed must be used to trigger activity.
Note that while a reading is being made, a character input can abort the reading, just as with normal interactive mode.
XDG_CACHE_HOME
Argyll tries to follow the XDG Base Directory Specification, and uses the XDG_CACHE_HOME environment variable to place per instrument calibration information (Eye-One Pro and ColorMunki instruments).
XDG_CONFIG_DIRS
XDG_DATA_DIRS
On Unix type operating systems, configuration and profiles for displays are placed relative to these environment variables.
See Performance Tuning for other variables.