изучить и изменить сигнальное действие (examine and change a signal action)
Ошибки (Error)
EFAULT act or oldact points to memory which is not a valid part
of the process address space.
EINVAL An invalid signal was specified. This will also be
generated if an attempt is made to change the action for
SIGKILL or SIGSTOP, which cannot be caught or ignored.