ref: 9910099b383e28a0a8b9b8c26ea99a5a2d77f5b3
dir: /include/bits/linux/sys.h/
#define O_RDONLY 0x00000000
#define O_WRONLY 0x00000001
#define O_RDWR 0x00000002
#define O_TRUNC 0x00000200
#define O_APPEND 0x00000400
#define O_CREAT 0x00000040
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, int);
extern int _sigaction(int, struct sigaction *, struct sigaction *);