POSIX 消息队列接收超时

Question

if((nbytes=mq_receive (qid_recv, (pchar_t)in_buffer, msg_buffer_size, NULL)) != -1) {
            printf("nbytes is %ld\n", nbytes);
}else{
     perror("recv_data");
     printf("nbytes is %ld\n", nbytes);

如果没有消息，如何从 mq_receive 退出 received.Is 有没有可能 timeout.Thanks 您的时间。

Answer 1

您可以使用mq_timedreceive函数。

Answer 2

除了mq_timedreceive()，你还可以在mq_open()打开队列时设置O_NONBLOCK。每 the mq_open() documentation:

O_NONBLOCK Determines whether an mq_send() or mq_receive() waits for resources or messages that are not currently available, or fails with errno set to EAGAIN; see mq_send and mq_receive for details.

根据 the mq_receive() documentation:

If the specified message queue is empty and O_NONBLOCK is set in the message queue description associated with mqdes, no message shall be removed from the queue, and mq_receive() shall return an error.

POSIX 消息队列接收超时

POSIX Message Queue Receive Timeout

c

queue

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