Xsct (X11 set color temperature) is a UNIX tool which allows you to set the color temperature of your screen. It is simpler than Redshift and f.lux.
Original code was published by Ted Unangst: http://www.tedunangst.com/flak/post/sct-set-color-temperature
Minor modifications were made in order to get sct to:
- compile on Ubuntu 14.04
- iterate over all screens of the default display and change the color temperature
- free the Display structure
- fix memleaks
- clean up code
- return EXIT_SUCCESS
Compile the code using the following command:
gcc -Wall -Wextra -Werror -pedantic -std=c99 -O2 -I /usr/X11R6/include xsct.c -o xsct -L /usr/X11R6/lib -lX11 -lXrandr -lm -s
Execute xsct using the following command:
./xsct 3700
The first parameter (3700 above) denotes the color temperature.
If xsct is called with parameter 0, the color temperature is set to 6500.
If xsct is called without parameters, the current display temperature is estimated.
Test xsct using the following command:
./xsct 3700 && ./xsct
The following website provides a table for the conversion between black-body temperatures and color pixel values: http://www.vendian.org/mncharity/dir3/blackbody/