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+zmq_msg_init_data(3)
+====================
+
+
+NAME
+----
+zmq_msg_init_data - initialises 0MQ message from the given data
+
+
+SYNOPSIS
+--------
+'typedef void (zmq_free_fn) (void *data, void *hint);'
+'int zmq_msg_init_data (zmq_msg_t *msg, void *data, size_t size, zmq_free_fn *ffn, void *hint);'
+
+
+DESCRIPTION
+-----------
+Initialise a message from a supplied buffer. Message isn't copied,
+instead 0MQ infrastructure takes ownership of the buffer located at address
+'data', 'size' bytes long. Deallocation function ('ffn') will be called once
+the data are not needed anymore. When using a static constant buffer, 'ffn' may
+be NULL to prevent subsequent deallocation. If needed, additional 'hint' can be
+passed to the initialisation function. It's an opaque pointer that will be
+later on passed to 'ffn' as a second argument.
+
+
+RETURN VALUE
+------------
+In case of success the function returns zero. Otherwise it returns -1 and
+sets 'errno' to the appropriate value.
+
+
+ERRORS
+------
+No errors are defined.
+
+
+EXAMPLE
+-------
+----
+void my_free (void *data, void *hint) {free (data);}
+
+ ...
+
+void *data = malloc (6);
+assert (data);
+memcpy (data, "ABCDEF", 6);
+zmq_msg_t msg;
+rc = zmq_msg_init_data (&msg, data, 6, my_free, NULL);
+assert (rc == 0);
+rc = zmq_send (s, &msg, 0);
+assert (rc == 0);
+----
+
+
+SEE ALSO
+--------
+linkzmq:zmq_msg_close[3]
+linkzmq:zmq_msg_init[3]
+linkzmq:zmq_msg_init_size[3]
+linkzmq:zmq_msg_data[3]
+linkzmq:zmq_msg_size[3]
+
+
+AUTHOR
+------
+Martin Sustrik <sustrik at 250bpm dot com>