s6-frontend
Software
skarnet.org
s6-frontend-helper-kill is a small utility to send numerical signals to a given list of pids. It is not meant to be called directly, although nothing bad will happen if you do. It is used in command lines crafted by s6 process kill instead of the POSIX kill program, because the latter does not support sending arbitrary numerical signals.
s6-frontend-helper-kill sig pids...