mq_receive.c 957 B

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  1. /*
  2. * mq_receive.c - functions for receiving from message queue.
  3. */
  4. #include <errno.h>
  5. #include <stddef.h>
  6. #include <sys/syscall.h>
  7. #include <mqueue.h>
  8. #ifdef __NR_mq_timedreceive
  9. #define __NR___syscall_mq_timedreceive __NR_mq_timedreceive
  10. static inline _syscall5(int, __syscall_mq_timedreceive, int, mqdes,
  11. char *, msg_ptr, size_t, msg_len, unsigned int *, msg_prio,
  12. const void *, abs_timeout);
  13. /*
  14. * Receive the oldest from highest priority messages.
  15. * Stop waiting if abs_timeout expires.
  16. */
  17. ssize_t mq_timedreceive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
  18. unsigned int *msg_prio,
  19. const struct timespec *abs_timeout)
  20. {
  21. return __syscall_mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio, abs_timeout);
  22. }
  23. /* Receive the oldest from highest priority messages */
  24. ssize_t mq_receive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
  25. unsigned int *msg_prio)
  26. {
  27. return mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio, NULL);
  28. }
  29. #endif