unistd.h

   1 #include <stddef.h>
   2
   3 #define SEEK_SET        0
   4 #define SEEK_CUR        1
   5 #define SEEK_END        2
   6
   7 extern char **environ;
   8
   9 int close(int fd);
  10 int write(int fd, void *buf, int n);
  11 int read(int fd, void *buf, int n);
  12 void _exit(int status);
  13
  14 #define R_OK            4
  15 #define W_OK            2
  16 #define X_OK            1
  17 #define F_OK            0
  18
  19 int access(char *name, int type);