ref: fe02e90431559e9440f10983457eb01eece016c0
dir: /include/bits/darwin/sys.h/
#define O_RDONLY 0x00000000 #define O_WRONLY 0x00000001 #define O_RDWR 0x00000002 #define O_TRUNC 0x00000400 #define O_APPEND 0x00000008 #define O_CREAT 0x00000200 typedef int pid_t; struct sigaction { void (*sa_handler)(int); int sa_mask; int sa_flags; }; extern pid_t _getpid(void); extern int _kill(pid_t pid, int signum); extern int _sigaction(int sig, struct sigaction *new, struct sigaction *old);