XS_GETMSGOPT(3) Crossroads I/O Manual XS_GETMSGOPT(3)NAMExs_getmsgopt - retrieve message option
SYNOPSIS
int xs_getmsgopt (xs_msg_t *message, int option_name, void
*option_value, size_t *option_len);
DESCRIPTION
The xs_getmsgopt() function shall retrieve the value for the option
specified by the option_name argument for the message pointed to by the
message argument, and store it in the buffer pointed to by the
option_value argument. The option_len argument is the size in bytes of
the buffer pointed to by option_value; upon successful completion
xs_getsockopt() shall modify the option_len argument to indicate the
actual size of the option value stored in the buffer.
The following options can be retrieved with the xs_getmsgopt()
function:
XS_MORE
Indicates that there are more message parts to follow after the
message. The type of this option is int. 0 means that this is the
last message part of a multipart message. 1 means that more message
parts will follow.
RETURN VALUE
The xs_getmsgopt() function shall return zero if successful. Otherwise
it shall return -1 and set errno to one of the values defined below.
ERRORS
EINVAL
The requested option option_name is unknown, or the requested
option_size or option_value is invalid, or the size of the buffer
pointed to by option_value, as specified by option_len, is
insufficient for storing the option value.
EXAMPLE
Receiving a multi-part message.
xs_msg_t part;
int more;
size_t more_size = sizeof (more);
while (true) {
/* Create an empty message to hold the message part */
int rc = xs_msg_init (&part);
assert (rc == 0);
/* Block until a message is available to be received from socket */
rc = xs_recvmsg (socket, &part, 0);
assert (rc != -1);
rc = getmsgopt (&part, XS_MORE, &more, &more_size);
assert (rc == 0);
if (more) {
fprintf (stderr, "more\n");
}
else {
fprintf (stderr, "end\n");
break;
}
xs_msg_close (part);
}
SEE ALSOxs_msg_data(3)xs_msg_init(3)xs_msg_init_size(3)xs_msg_init_data(3)xs_msg_close(3)xs(7)AUTHORS
This manual page was written by Chuck Remes <cremes@mac.com[1]>.
NOTES
1. cremes@mac.com
mailto:cremes@mac.com
Crossroads I/O 1.2.0 02/17/2016 XS_GETMSGOPT(3)
