zmq_msg_init_data(3)

1ZMQ_MSG_INIT_DATA(3)              0MQ Manual              ZMQ_MSG_INIT_DATA(3)
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NAME

6       zmq_msg_init_data - initialise 0MQ message from a supplied buffer
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SYNOPSIS

9       typedef void (zmq_free_fn) (void *data, void *hint);
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11       int zmq_msg_init_data (zmq_msg_t *msg, void *data, size_t size,
12       zmq_free_fn *ffn, void *hint);
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DESCRIPTION

15       The zmq_msg_init_data() function shall initialise the message object
16       referenced by msg to represent the content referenced by the buffer
17       located at address data, size bytes long. No copy of data shall be
18       performed and 0MQ shall take ownership of the supplied buffer.
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20       If provided, the deallocation function ffn shall be called once the
21       data buffer is no longer required by 0MQ, with the data and hint
22       arguments supplied to zmq_msg_init_data().
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24           Caution
25           Never access zmq_msg_t members directly, instead always use the
26           zmq_msg family of functions.
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28           Caution
29           The functions zmq_msg_init(), zmq_msg_init_data() and
30           zmq_msg_init_size() are mutually exclusive. Never initialize the
31           same zmq_msg_t twice.
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RETURN VALUE

34       The zmq_msg_init_data() function shall return zero if successful.
35       Otherwise it shall return -1 and set errno to one of the values defined
36       below.
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ERRORS

39       No errors are defined.
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EXAMPLE

42       Initialising a message from a supplied buffer.
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44           void my_free (void *data, void *hint)
45           {
46               free (data);
47           }
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49               /*  ...  */
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51           void *data = malloc (6);
52           assert (data);
53           memcpy (data, "ABCDEF", 6);
54           zmq_msg_t msg;
55           rc = zmq_msg_init_data (&msg, data, 6, my_free, NULL);
56           assert (rc == 0);
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AUTHORS

64       This 0MQ manual page was written by Martin Sustrik
65       <sustrik@250bpm.com[1]> and Martin Lucina <mato@kotelna.sk[2]>.
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NOTES

68        1. sustrik@250bpm.com
69           mailto:sustrik@250bpm.com
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71        2. mato@kotelna.sk
72           mailto:mato@kotelna.sk
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760MQ 2.1.4                         03/30/2011              ZMQ_MSG_INIT_DATA(3)