#define POLLIN      0x001       /* There is data to read.  */

#define POLLPRI     0x002       /* There is urgent data to read.  */

#define POLLOUT     0x004       /* Writing now will not block.  */

 

#if defined __USE_XOPEN || defined __USE_XOPEN2K8

/* These values are defined in XPG4.2.  */

# define POLLRDNORM 0x040       /* Normal data may be read.  */

# define POLLRDBAND 0x080       /* Priority data may be read.  */

# define POLLWRNORM 0x100       /* Writing now will not block.  */

# define POLLWRBAND 0x200       /* Priority data may be written.  */

#endif

 

#ifdef __USE_GNU

/* These are extensions for Linux.  */

# define POLLMSG    0x400

# define POLLREMOVE 0x1000

# define POLLRDHUP  0x2000

#endif

 

/* Event types always implicitly polled for.  These bits need not be set in

   `events', but they will appear in `revents' to indicate the status of

   the file descriptor.  */

#define POLLERR     0x008       /* Error condition.  */

#define POLLHUP     0x010       /* Hung up.  */

#define POLLNVAL    0x020       /* Invalid polling request.  */