When we have siginterrupt(), use it to disable restarting interrupted

system calls.

Modules/signalmodule.c

@@ -152,6 +152,9 @@ signal_handler(sig_num)
 		   to the Python handler... */
 		return;
 	}
+#endif
+#ifdef HAVE_SIGINTERRUPT
+	siginterrupt(sig_num, 1);
 #endif
 	(void)signal(sig_num, &signal_handler);
 }
@@ -240,6 +243,9 @@ signal_signal(self, args)
 	}
 	else
 		func = signal_handler;
+#ifdef HAVE_SIGINTERRUPT
+	siginterrupt(sig_num, 1);
+#endif
 	if (signal(sig_num, func) == SIG_ERR) {
 		PyErr_SetFromErrno(PyExc_RuntimeError);
 		return NULL;