*-F* _level_::
This option configures a system call filter when *chronyd* is compiled with
support for the Linux secure computing (seccomp) facility. In level 1 the
-process is killed when a forbidden system call is made, in level -1 the SYSSIG
+process is killed when a forbidden system call is made, in level -1 the SIGSYS
signal is thrown instead and in level 0 the filter is disabled (default 0).
+
It's recommended to enable the filter only when it's known to work on the