gSocketReceive
and gSocketReceiveFrom
.gSocketReceiveMessage(object, flags = 0, cancellable = NULL, .errwarn = TRUE)
object
GSocket
flags
GSocketMsgFlags
flagscancellable
GCancellable
or NULL
address
GSocketAddress
pointer, or NULL
vectors
GInputVector
structsmessages
GSocketControlMessages
, or NULL
num.messages
messages
, or NULL
error
GError
pointer, or NULL
address
is non-NULL
then address
will be set equal to the
source the received packet.
vector
must point to a list of GInputVector
structs and
num.vectors
must be the length of this list. These structs
describe the buffers that received data will be scattered into.
If num.vectors
is -1, then vectors
is assumed to be terminated
by a GInputVector
with a NULL
buffer pointer.
As a special case, if num.vectors
is 0 (in which case, vectors
may of course be NULL
), then a single byte is received and
discarded. This is to facilitate the common practice of sending a
single '\0' byte for the purposes of transferring ancillary data.
messages
, if non-NULL
, will be set to point to a newly-allocated
array of GSocketControlMessage
instances. These correspond to the
control messages received from the kernel, one
GSocketControlMessage
per message from the kernel. If
messages
is NULL
, any control messages received will be
discarded.
num.messages
, if non-NULL
, will be set to the number of control
messages received.
If both messages
and num.messages
are non-NULL
, then
num.messages
gives the number of GSocketControlMessage
instances
in messages
(ie: not including the NULL
terminator).
flags
is an in/out parameter. The commonly available arguments
for this are available in the GSocketMsgFlags
enum, but the
values there are the same as the system values, and the flags
are passed in as-is, so you can pass in system-specific flags too
(and gSocketReceiveMessage
may pass system-specific flags out).
As with gSocketReceive
, data may be discarded if socket
is
G_SOCKET_TYPE_DATAGRAM
or G_SOCKET_TYPE_SEQPACKET
and you do not
provide enough buffer space to read a complete message. You can pass
G_SOCKET_MSG_PEEK
in flags
to peek at the current message without
removing it from the receive queue, but there is no portable way to find
out the length of the message other than by reading it into a
sufficiently-large buffer.
If the socket is in blocking mode the call will block until there
is some data to receive or there is an error. If there is no data
available and the socket is in non-blocking mode, a
G_IO_ERROR_WOULD_BLOCK
error will be returned. To be notified when
data is available, wait for the G_IO_IN
condition.
On error -1 is returned and error
is set accordingly.
Since 2.22