|| ((addr) & 0xfff00000) == 0xac100000 /* 172.16.x.x */ \
|| ((addr) & 0xffff0000) == 0xc0a80000) /* 192.168.x.x */
-#define process_exists(n) (kill(0, (n)) == 0 || errno != ESRCH)
+#define process_exists(n) (kill((n), 0) == 0 || errno != ESRCH)
void
mp_check_options()