ref: 7a0162ccab2a49e56e2da35d3929fab28b7173cf
dir: /src/libc/syscall.h/
extern int _brk(void *); extern void _exit(int); extern int _close(int); extern int _open(const char *, int, int); extern int _read(int, void *, size_t); extern int _unlink(const char *); extern int _write(int, void *, size_t); extern int _access(const char *, int); extern long _lseek(int, long, int);