SIGKILL 46 usr/lib/posix/signal/sigaction.c signum == SIGSTOP || signum == SIGKILL) { SIGKILL 40 usr/lib/posix/signal/signal.c if (sig <= 0 || sig >= NSIG || sig == SIGSTOP || sig == SIGKILL) { SIGKILL 66 usr/lib/posix/signal/sigprocmask.c __sig_mask &= ~(sigmask(SIGSTOP) | sigmask(SIGKILL));