XS_MSG_INIT_DATA(3) Crossroads I/O Manual XS_MSG_INIT_DATA(3)NAME
xs_msg_init_data - initialise Crossroads message from a supplied buffer
SYNOPSIS
typedef void (xs_free_fn) (void *data, void *hint);
int xs_msg_init_data (xs_msg_t *msg, void *data, size_t size,
xs_free_fn *ffn, void *hint);
DESCRIPTION
The xs_msg_init_data() function shall initialise the message object
referenced by msg to represent the content referenced by the buffer
located at address data, size bytes long. No copy of data shall be
performed and the library shall take ownership of the supplied buffer.
If provided, the deallocation function ffn shall be called once the
data buffer is no longer required by the library, with the data and
hint arguments supplied to xs_msg_init_data().
Caution
Never access xs_msg_t members directly, instead always use the
xs_msg family of functions.
Caution
The deallocation function ffn needs to be thread-safe, since it
will be called from an arbitrary thread.
Caution
The functions xs_msg_init(), xs_msg_init_data() and
xs_msg_init_size() are mutually exclusive. Never initialize the
same xs_msg_t twice.
RETURN VALUE
The xs_msg_init_data() function shall return zero if successful.
Otherwise it shall return -1 and set errno to one of the values defined
below.
ERRORS
ENOMEM
Insufficient storage space is available.
EXAMPLE
Initialising a message from a supplied buffer.
void my_free (void *data, void *hint)
{
free (data);
}
/* ... */
void *data = malloc (6);
assert (data);
memcpy (data, "ABCDEF", 6);
xs_msg_t msg;
rc = xs_msg_init_data (&msg, data, 6, my_free, NULL);
assert (rc == 0);
SEE ALSOxs_msg_init_size(3)xs_msg_init(3)xs_msg_close(3)xs_msg_data(3)xs_msg_size(3)xs(7)AUTHORS
The Crossroads documentation was written by Martin Sustrik
<sustrik@250bpm.com[1]> and Martin Lucina <martin@lucina.net[2]>.
NOTES
1. sustrik@250bpm.com
mailto:sustrik@250bpm.com
2. martin@lucina.net
mailto:martin@lucina.net
Crossroads I/O 1.2.0 02/17/2016 XS_MSG_INIT_DATA(3)