control_client_sighandler
ssh_signal(SIGHUP, control_client_sighandler);
ssh_signal(SIGINT, control_client_sighandler);
ssh_signal(SIGTERM, control_client_sighandler);
ssh_signal(SIGHUP, control_client_sighandler);
ssh_signal(SIGINT, control_client_sighandler);
ssh_signal(SIGTERM, control_client_sighandler);