On fade in, query active setting and start from there. (requires libred>=1.1)
Use bus for changing settings and CRTCs online.
Add "-t ?" and "-t get" for getting the current temperature. (requires libred>=1.1)
On SIGUSR1, fade out without terminating
On SIGUSR2, fade in
Add PF_UNIX SOCK_DGRAM socket with abstract address @/proc/<pid>/radharc for IPC