ref: ec4c79f3a6ed97ec0c407a870827382cbefb1166
dir: /include/bits/linux/sys.h/
#define O_RDONLY 0x00000000 #define O_WRONLY 0x00000001 #define O_RDWR 0x00000002 #define O_ACCMODE 0x00000003 #define O_CLOEXEC 0x00080000 #define O_TRUNC 0x00000200 #define O_APPEND 0x00000400 #define O_EXCL 0x00000080 #define O_CREAT 0x00000040 #define AT_FDCWD -100 #define CLOCKS_PER_SEC ((clock_t) 1000000) #define RUSAGE_SELF 0 #define F_OK 0 #define X_OK 1 #define R_OK 4 #define W_OK 2 typedef int pid_t; struct sigaction; struct rusage; extern int _execve(char *, char *[], char *[]); extern int _fork(void); extern pid_t _getpid(void); extern int _kill(pid_t, int); extern int _sigaction(int, struct sigaction *, struct sigaction *); extern pid_t _wait4(pid_t, int *, int, struct rusage *); extern pid_t _waitpid(pid_t, int *, int);