Functions
GSocketSourceFunc ()
gboolean
(*GSocketSourceFunc) (GSocket *socket,
GIOCondition condition,
gpointer user_data);
This is the function type of the callback used for the GSource
returned by g_socket_create_source().
Returns
it should return FALSE if the source should be removed.
Since: 2.22
g_socket_new ()
GSocket *
g_socket_new (GSocketFamily family,
GSocketType type,
GSocketProtocol protocol,
GError **error);
Creates a new GSocket with the defined family, type and protocol.
If protocol
is 0 (G_SOCKET_PROTOCOL_DEFAULT) the default protocol type
for the family and type is used.
The protocol
is a family and type specific int that specifies what
kind of protocol to use. GSocketProtocol lists several common ones.
Many families only support one protocol, and use 0 for this, others
support several and using 0 means to use the default protocol for
the family and type.
The protocol id is passed directly to the operating
system, so you can use protocols not listed in GSocketProtocol if you
know the protocol number used for it.
Returns
a GSocket or NULL on error.
Free the returned object with g_object_unref().
Since: 2.22
g_socket_new_from_fd ()
GSocket *
g_socket_new_from_fd (gint fd,
GError **error);
Creates a new GSocket from a native file descriptor
or winsock SOCKET handle.
This reads all the settings from the file descriptor so that
all properties should work. Note that the file descriptor
will be set to non-blocking mode, independent on the blocking
mode of the GSocket.
On success, the returned GSocket takes ownership of fd
. On failure, the
caller must close fd
themselves.
Since GLib 2.46, it is no longer a fatal error to call this on a non-socket
descriptor. Instead, a GError will be set with code G_IO_ERROR_FAILED
Returns
a GSocket or NULL on error.
Free the returned object with g_object_unref().
Since: 2.22
g_socket_bind ()
gboolean
g_socket_bind (GSocket *socket,
GSocketAddress *address,
gboolean allow_reuse,
GError **error);
When a socket is created it is attached to an address family, but it
doesn't have an address in this family. g_socket_bind() assigns the
address (sometimes called name) of the socket.
It is generally required to bind to a local address before you can
receive connections. (See g_socket_listen() and g_socket_accept() ).
In certain situations, you may also want to bind a socket that will be
used to initiate connections, though this is not normally required.
If socket
is a TCP socket, then allow_reuse
controls the setting
of the SO_REUSEADDR socket option; normally it should be TRUE for
server sockets (sockets that you will eventually call
g_socket_accept() on), and FALSE for client sockets. (Failing to
set this flag on a server socket may cause g_socket_bind() to return
G_IO_ERROR_ADDRESS_IN_USE if the server program is stopped and then
immediately restarted.)
If socket
is a UDP socket, then allow_reuse
determines whether or
not other UDP sockets can be bound to the same address at the same
time. In particular, you can have several UDP sockets bound to the
same address, and they will all receive all of the multicast and
broadcast packets sent to that address. (The behavior of unicast
UDP packets to an address with multiple listeners is not defined.)
Returns
TRUE on success, FALSE on error.
Since: 2.22
g_socket_listen ()
gboolean
g_socket_listen (GSocket *socket,
GError **error);
Marks the socket as a server socket, i.e. a socket that is used
to accept incoming requests using g_socket_accept().
Before calling this the socket must be bound to a local address using
g_socket_bind().
To set the maximum amount of outstanding clients, use
g_socket_set_listen_backlog().
Returns
TRUE on success, FALSE on error.
Since: 2.22
g_socket_accept ()
GSocket *
g_socket_accept (GSocket *socket,
GCancellable *cancellable,
GError **error);
Accept incoming connections on a connection-based socket. This removes
the first outstanding connection request from the listening socket and
creates a GSocket object for it.
The socket
must be bound to a local address with g_socket_bind() and
must be listening for incoming connections (g_socket_listen()).
If there are no outstanding connections then the operation will block
or return G_IO_ERROR_WOULD_BLOCK if non-blocking I/O is enabled.
To be notified of an incoming connection, wait for the G_IO_IN condition.
Returns
a new GSocket, or NULL on error.
Free the returned object with g_object_unref().
[transfer full]
Since: 2.22
g_socket_connect ()
gboolean
g_socket_connect (GSocket *socket,
GSocketAddress *address,
GCancellable *cancellable,
GError **error);
Connect the socket to the specified remote address.
For connection oriented socket this generally means we attempt to make
a connection to the address
. For a connection-less socket it sets
the default address for g_socket_send() and discards all incoming datagrams
from other sources.
Generally connection oriented sockets can only connect once, but
connection-less sockets can connect multiple times to change the
default address.
If the connect call needs to do network I/O it will block, unless
non-blocking I/O is enabled. Then G_IO_ERROR_PENDING is returned
and the user can be notified of the connection finishing by waiting
for the G_IO_OUT condition. The result of the connection must then be
checked with g_socket_check_connect_result().
Returns
TRUE if connected, FALSE on error.
Since: 2.22
g_socket_check_connect_result ()
gboolean
g_socket_check_connect_result (GSocket *socket,
GError **error);
Checks and resets the pending connect error for the socket.
This is used to check for errors when g_socket_connect() is
used in non-blocking mode.
Returns
TRUE if no error, FALSE otherwise, setting error
to the error
Since: 2.22
g_socket_receive ()
gssize
g_socket_receive (GSocket *socket,
gchar *buffer,
gsize size,
GCancellable *cancellable,
GError **error);
Receive data (up to size
bytes) from a socket. This is mainly used by
connection-oriented sockets; it is identical to g_socket_receive_from()
with address
set to NULL.
For G_SOCKET_TYPE_DATAGRAM and G_SOCKET_TYPE_SEQPACKET sockets,
g_socket_receive() will always read either 0 or 1 complete messages from
the socket. If the received message is too large to fit in buffer
, then
the data beyond size
bytes will be discarded, without any explicit
indication that this has occurred.
For G_SOCKET_TYPE_STREAM sockets, g_socket_receive() can return any
number of bytes, up to size
. If more than size
bytes have been
received, the additional data will be returned in future calls to
g_socket_receive().
If the socket is in blocking mode the call will block until there
is some data to receive, the connection is closed, 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.
Returns
Number of bytes read, or 0 if the connection was closed by
the peer, or -1 on error
Since: 2.22
g_socket_receive_from ()
gssize
g_socket_receive_from (GSocket *socket,
GSocketAddress **address,
gchar *buffer,
gsize size,
GCancellable *cancellable,
GError **error);
Receive data (up to size
bytes) from a socket.
If address
is non-NULL then address
will be set equal to the
source address of the received packet.
address
is owned by the caller.
See g_socket_receive() for additional information.
Returns
Number of bytes read, or 0 if the connection was closed by
the peer, or -1 on error
Since: 2.22
g_socket_receive_message ()
gssize
g_socket_receive_message (GSocket *socket,
GSocketAddress **address,
GInputVector *vectors,
gint num_vectors,
GSocketControlMessage ***messages,
gint *num_messages,
gint *flags,
GCancellable *cancellable,
GError **error);
Receive data from a socket. For receiving multiple messages, see
g_socket_receive_messages(); for easier use, see
g_socket_receive() and g_socket_receive_from().
If address
is non-NULL then address
will be set equal to the
source address of the received packet.
address
is owned by the caller.
vector
must point to an array of GInputVector structs and
num_vectors
must be the length of this array. 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 or NULL if no such
messages was received. These correspond to the control messages
received from the kernel, one GSocketControlMessage per message
from the kernel. This array is NULL-terminated and must be freed
by the caller using g_free() after calling g_object_unref() on each
element. 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 g_socket_receive_message() may pass system-specific flags out).
Flags passed in to the parameter affect the receive operation; flags returned
out of it are relevant to the specific returned message.
As with g_socket_receive(), 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, the connection is closed, 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.
Returns
Number of bytes read, or 0 if the connection was closed by
the peer, or -1 on error
Since: 2.22
g_socket_receive_messages ()
gint
g_socket_receive_messages (GSocket *socket,
GInputMessage *messages,
guint num_messages,
gint flags,
GCancellable *cancellable,
GError **error);
Receive multiple data messages from socket
in one go. This is the most
complicated and fully-featured version of this call. For easier use, see
g_socket_receive(), g_socket_receive_from(), and g_socket_receive_message().
messages
must point to an array of GInputMessage structs and
num_messages
must be the length of this array. Each GInputMessage
contains a pointer to an array of GInputVector structs describing the
buffers that the data received in each message will be written to. Using
multiple GInputVectors is more memory-efficient than manually copying data
out of a single buffer to multiple sources, and more system-call-efficient
than making multiple calls to g_socket_receive(), such as in scenarios where
a lot of data packets need to be received (e.g. high-bandwidth video
streaming over RTP/UDP).
flags
modify how all messages are received. 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. These
flags affect the overall receive operation. Flags affecting individual
messages are returned in GInputMessage.flags.
The other members of GInputMessage are treated as described in its
documentation.
If “blocking” is TRUE the call will block until num_messages
have
been received, or the end of the stream is reached.
If “blocking” is FALSE the call will return up to num_messages
without blocking, or G_IO_ERROR_WOULD_BLOCK if no messages are queued in the
operating system to be received.
In blocking mode, if “timeout” is positive and is reached before any
messages are received, G_IO_ERROR_TIMED_OUT is returned, otherwise up to
num_messages
are returned. (Note: This is effectively the
behaviour of MSG_WAITFORONE with recvmmsg().)
To be notified when messages are available, wait for the
G_IO_IN condition. Note though that you may still receive
G_IO_ERROR_WOULD_BLOCK from g_socket_receive_messages() even if you were
previously notified of a G_IO_IN condition.
If the remote peer closes the connection, any messages queued in the
operating system will be returned, and subsequent calls to
g_socket_receive_messages() will return 0 (with no error set).
On error -1 is returned and error
is set accordingly. An error will only
be returned if zero messages could be received; otherwise the number of
messages successfully received before the error will be returned.
Returns
number of messages received, or -1 on error. Note that the number
of messages received may be smaller than num_messages
if in non-blocking
mode, if the peer closed the connection, or if num_messages
was larger than UIO_MAXIOV (1024), in which case the caller may re-try
to receive the remaining messages.
Since: 2.48
g_socket_receive_with_blocking ()
gssize
g_socket_receive_with_blocking (GSocket *socket,
gchar *buffer,
gsize size,
gboolean blocking,
GCancellable *cancellable,
GError **error);
This behaves exactly the same as g_socket_receive(), except that
the choice of blocking or non-blocking behavior is determined by
the blocking
argument rather than by socket
's properties.
Returns
Number of bytes read, or 0 if the connection was closed by
the peer, or -1 on error
Since: 2.26
g_socket_send ()
gssize
g_socket_send (GSocket *socket,
const gchar *buffer,
gsize size,
GCancellable *cancellable,
GError **error);
Tries to send size
bytes from buffer
on the socket. This is
mainly used by connection-oriented sockets; it is identical to
g_socket_send_to() with address
set to NULL.
If the socket is in blocking mode the call will block until there is
space for the data in the socket queue. If there is no space available
and the socket is in non-blocking mode a G_IO_ERROR_WOULD_BLOCK error
will be returned. To be notified when space is available, wait for the
G_IO_OUT condition. Note though that you may still receive
G_IO_ERROR_WOULD_BLOCK from g_socket_send() even if you were previously
notified of a G_IO_OUT condition. (On Windows in particular, this is
very common due to the way the underlying APIs work.)
On error -1 is returned and error
is set accordingly.
Returns
Number of bytes written (which may be less than size
), or -1
on error
Since: 2.22
g_socket_send_to ()
gssize
g_socket_send_to (GSocket *socket,
GSocketAddress *address,
const gchar *buffer,
gsize size,
GCancellable *cancellable,
GError **error);
Tries to send size
bytes from buffer
to address
. If address
is
NULL then the message is sent to the default receiver (set by
g_socket_connect()).
See g_socket_send() for additional information.
Returns
Number of bytes written (which may be less than size
), or -1
on error
Since: 2.22
g_socket_send_message ()
gssize
g_socket_send_message (GSocket *socket,
GSocketAddress *address,
GOutputVector *vectors,
gint num_vectors,
GSocketControlMessage **messages,
gint num_messages,
gint flags,
GCancellable *cancellable,
GError **error);
Send data to address
on socket
. For sending multiple messages see
g_socket_send_messages(); for easier use, see
g_socket_send() and g_socket_send_to().
If address
is NULL then the message is sent to the default receiver
(set by g_socket_connect()).
vectors
must point to an array of GOutputVector structs and
num_vectors
must be the length of this array. (If num_vectors
is -1,
then vectors
is assumed to be terminated by a GOutputVector with a
NULL buffer pointer.) The GOutputVector structs describe the buffers
that the sent data will be gathered from. Using multiple
GOutputVectors is more memory-efficient than manually copying
data from multiple sources into a single buffer, and more
network-efficient than making multiple calls to g_socket_send().
messages
, if non-NULL, is taken to point to an array of num_messages
GSocketControlMessage instances. These correspond to the control
messages to be sent on the socket.
If num_messages
is -1 then messages
is treated as a NULL-terminated
array.
flags
modify how the message is sent. 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.
If the socket is in blocking mode the call will block until there is
space for the data in the socket queue. If there is no space available
and the socket is in non-blocking mode a G_IO_ERROR_WOULD_BLOCK error
will be returned. To be notified when space is available, wait for the
G_IO_OUT condition. Note though that you may still receive
G_IO_ERROR_WOULD_BLOCK from g_socket_send() even if you were previously
notified of a G_IO_OUT condition. (On Windows in particular, this is
very common due to the way the underlying APIs work.)
On error -1 is returned and error
is set accordingly.
Returns
Number of bytes written (which may be less than size
), or -1
on error
Since: 2.22
g_socket_send_message_with_timeout ()
GPollableReturn
g_socket_send_message_with_timeout (GSocket *socket,
GSocketAddress *address,
const GOutputVector *vectors,
gint num_vectors,
GSocketControlMessage **messages,
gint num_messages,
gint flags,
gint64 timeout_us,
gsize *bytes_written,
GCancellable *cancellable,
GError **error);
This behaves exactly the same as g_socket_send_message(), except that
the choice of timeout behavior is determined by the timeout_us
argument
rather than by socket
's properties.
On error G_POLLABLE_RETURN_FAILED is returned and error
is set accordingly, or
if the socket is currently not writable G_POLLABLE_RETURN_WOULD_BLOCK is
returned. bytes_written
will contain 0 in both cases.
Since: 2.60
g_socket_send_messages ()
gint
g_socket_send_messages (GSocket *socket,
GOutputMessage *messages,
guint num_messages,
gint flags,
GCancellable *cancellable,
GError **error);
Send multiple data messages from socket
in one go. This is the most
complicated and fully-featured version of this call. For easier use, see
g_socket_send(), g_socket_send_to(), and g_socket_send_message().
messages
must point to an array of GOutputMessage structs and
num_messages
must be the length of this array. Each GOutputMessage
contains an address to send the data to, and a pointer to an array of
GOutputVector structs to describe the buffers that the data to be sent
for each message will be gathered from. Using multiple GOutputVectors is
more memory-efficient than manually copying data from multiple sources
into a single buffer, and more network-efficient than making multiple
calls to g_socket_send(). Sending multiple messages in one go avoids the
overhead of making a lot of syscalls in scenarios where a lot of data
packets need to be sent (e.g. high-bandwidth video streaming over RTP/UDP),
or where the same data needs to be sent to multiple recipients.
flags
modify how the message is sent. 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.
If the socket is in blocking mode the call will block until there is
space for all the data in the socket queue. If there is no space available
and the socket is in non-blocking mode a G_IO_ERROR_WOULD_BLOCK error
will be returned if no data was written at all, otherwise the number of
messages sent will be returned. To be notified when space is available,
wait for the G_IO_OUT condition. Note though that you may still receive
G_IO_ERROR_WOULD_BLOCK from g_socket_send() even if you were previously
notified of a G_IO_OUT condition. (On Windows in particular, this is
very common due to the way the underlying APIs work.)
On error -1 is returned and error
is set accordingly. An error will only
be returned if zero messages could be sent; otherwise the number of messages
successfully sent before the error will be returned.
Returns
number of messages sent, or -1 on error. Note that the number of
messages sent may be smaller than num_messages
if the socket is
non-blocking or if num_messages
was larger than UIO_MAXIOV (1024),
in which case the caller may re-try to send the remaining messages.
Since: 2.44
g_socket_send_with_blocking ()
gssize
g_socket_send_with_blocking (GSocket *socket,
const gchar *buffer,
gsize size,
gboolean blocking,
GCancellable *cancellable,
GError **error);
This behaves exactly the same as g_socket_send(), except that
the choice of blocking or non-blocking behavior is determined by
the blocking
argument rather than by socket
's properties.
Returns
Number of bytes written (which may be less than size
), or -1
on error
Since: 2.26
g_socket_close ()
gboolean
g_socket_close (GSocket *socket,
GError **error);
Closes the socket, shutting down any active connection.
Closing a socket does not wait for all outstanding I/O operations
to finish, so the caller should not rely on them to be guaranteed
to complete even if the close returns with no error.
Once the socket is closed, all other operations will return
G_IO_ERROR_CLOSED. Closing a socket multiple times will not
return an error.
Sockets will be automatically closed when the last reference
is dropped, but you might want to call this function to make sure
resources are released as early as possible.
Beware that due to the way that TCP works, it is possible for
recently-sent data to be lost if either you close a socket while the
G_IO_IN condition is set, or else if the remote connection tries to
send something to you after you close the socket but before it has
finished reading all of the data you sent. There is no easy generic
way to avoid this problem; the easiest fix is to design the network
protocol such that the client will never send data "out of turn".
Another solution is for the server to half-close the connection by
calling g_socket_shutdown() with only the shutdown_write
flag set,
and then wait for the client to notice this and close its side of the
connection, after which the server can safely call g_socket_close().
(This is what GTcpConnection does if you call
g_tcp_connection_set_graceful_disconnect(). But of course, this
only works if the client will close its connection after the server
does.)
Returns
TRUE on success, FALSE on error
Since: 2.22
g_socket_is_closed ()
gboolean
g_socket_is_closed (GSocket *socket);
Checks whether a socket is closed.
Returns
TRUE if socket is closed, FALSE otherwise
Since: 2.22
g_socket_shutdown ()
gboolean
g_socket_shutdown (GSocket *socket,
gboolean shutdown_read,
gboolean shutdown_write,
GError **error);
Shut down part or all of a full-duplex connection.
If shutdown_read
is TRUE then the receiving side of the connection
is shut down, and further reading is disallowed.
If shutdown_write
is TRUE then the sending side of the connection
is shut down, and further writing is disallowed.
It is allowed for both shutdown_read
and shutdown_write
to be TRUE.
One example where it is useful to shut down only one side of a connection is
graceful disconnect for TCP connections where you close the sending side,
then wait for the other side to close the connection, thus ensuring that the
other side saw all sent data.
Returns
TRUE on success, FALSE on error
Since: 2.22
g_socket_is_connected ()
gboolean
g_socket_is_connected (GSocket *socket);
Check whether the socket is connected. This is only useful for
connection-oriented sockets.
If using g_socket_shutdown(), this function will return TRUE until the
socket has been shut down for reading and writing. If you do a non-blocking
connect, this function will not return TRUE until after you call
g_socket_check_connect_result().
Returns
TRUE if socket is connected, FALSE otherwise.
Since: 2.22
g_socket_create_source ()
GSource *
g_socket_create_source (GSocket *socket,
GIOCondition condition,
GCancellable *cancellable);
Creates a GSource that can be attached to a GMainContext to monitor
for the availability of the specified condition
on the socket. The GSource
keeps a reference to the socket
.
The callback on the source is of the GSocketSourceFunc type.
It is meaningless to specify G_IO_ERR or G_IO_HUP in condition
;
these conditions will always be reported output if they are true.
cancellable
if not NULL can be used to cancel the source, which will
cause the source to trigger, reporting the current condition (which
is likely 0 unless cancellation happened at the same time as a
condition change). You can check for this in the callback using
g_cancellable_is_cancelled().
If socket
has a timeout set, and it is reached before condition
occurs, the source will then trigger anyway, reporting G_IO_IN or
G_IO_OUT depending on condition
. However, socket
will have been
marked as having had a timeout, and so the next GSocket I/O method
you call will then fail with a G_IO_ERROR_TIMED_OUT.
[skip]
Returns
a newly allocated GSource, free with g_source_unref().
[transfer full]
Since: 2.22
g_socket_condition_check ()
GIOCondition
g_socket_condition_check (GSocket *socket,
GIOCondition condition);
Checks on the readiness of socket
to perform operations.
The operations specified in condition
are checked for and masked
against the currently-satisfied conditions on socket
. The result
is returned.
Note that on Windows, it is possible for an operation to return
G_IO_ERROR_WOULD_BLOCK even immediately after
g_socket_condition_check() has claimed that the socket is ready for
writing. Rather than calling g_socket_condition_check() and then
writing to the socket if it succeeds, it is generally better to
simply try writing to the socket right away, and try again later if
the initial attempt returns G_IO_ERROR_WOULD_BLOCK.
It is meaningless to specify G_IO_ERR or G_IO_HUP in condition;
these conditions will always be set in the output if they are true.
This call never blocks.
Returns
the GIOCondition
mask of the current state
Since: 2.22
g_socket_condition_wait ()
gboolean
g_socket_condition_wait (GSocket *socket,
GIOCondition condition,
GCancellable *cancellable,
GError **error);
Waits for condition
to become true on socket
. When the condition
is met, TRUE is returned.
If cancellable
is cancelled before the condition is met, or if the
socket has a timeout set and it is reached before the condition is
met, then FALSE is returned and error
, if non-NULL, is set to
the appropriate value (G_IO_ERROR_CANCELLED or
G_IO_ERROR_TIMED_OUT).
See also g_socket_condition_timed_wait().
Returns
TRUE if the condition was met, FALSE otherwise
Since: 2.22
g_socket_condition_timed_wait ()
gboolean
g_socket_condition_timed_wait (GSocket *socket,
GIOCondition condition,
gint64 timeout_us,
GCancellable *cancellable,
GError **error);
Waits for up to timeout_us
microseconds for condition
to become true
on socket
. If the condition is met, TRUE is returned.
If cancellable
is cancelled before the condition is met, or if
timeout_us
(or the socket's “timeout”) is reached before the
condition is met, then FALSE is returned and error
, if non-NULL,
is set to the appropriate value (G_IO_ERROR_CANCELLED or
G_IO_ERROR_TIMED_OUT).
If you don't want a timeout, use g_socket_condition_wait().
(Alternatively, you can pass -1 for timeout_us
.)
Note that although timeout_us
is in microseconds for consistency with
other GLib APIs, this function actually only has millisecond
resolution, and the behavior is undefined if timeout_us
is not an
exact number of milliseconds.
Returns
TRUE if the condition was met, FALSE otherwise
Since: 2.32
g_socket_get_available_bytes ()
gssize
g_socket_get_available_bytes (GSocket *socket);
Get the amount of data pending in the OS input buffer, without blocking.
If socket
is a UDP or SCTP socket, this will return the size of
just the next packet, even if additional packets are buffered after
that one.
Note that on Windows, this function is rather inefficient in the
UDP case, and so if you know any plausible upper bound on the size
of the incoming packet, it is better to just do a
g_socket_receive() with a buffer of that size, rather than calling
g_socket_get_available_bytes() first and then doing a receive of
exactly the right size.
Returns
the number of bytes that can be read from the socket
without blocking or truncating, or -1 on error.
Since: 2.32
g_socket_set_listen_backlog ()
void
g_socket_set_listen_backlog (GSocket *socket,
gint backlog);
Sets the maximum number of outstanding connections allowed
when listening on this socket. If more clients than this are
connecting to the socket and the application is not handling them
on time then the new connections will be refused.
Note that this must be called before g_socket_listen() and has no
effect if called after that.
Since: 2.22
g_socket_get_listen_backlog ()
gint
g_socket_get_listen_backlog (GSocket *socket);
Gets the listen backlog setting of the socket. For details on this,
see g_socket_set_listen_backlog().
Returns
the maximum number of pending connections.
Since: 2.22
g_socket_get_blocking ()
gboolean
g_socket_get_blocking (GSocket *socket);
Gets the blocking mode of the socket. For details on blocking I/O,
see g_socket_set_blocking().
Returns
TRUE if blocking I/O is used, FALSE otherwise.
Since: 2.22
g_socket_set_blocking ()
void
g_socket_set_blocking (GSocket *socket,
gboolean blocking);
Sets the blocking mode of the socket. In blocking mode
all operations (which don’t take an explicit blocking parameter) block until
they succeed or there is an error. In
non-blocking mode all functions return results immediately or
with a G_IO_ERROR_WOULD_BLOCK error.
All sockets are created in blocking mode. However, note that the
platform level socket is always non-blocking, and blocking mode
is a GSocket level feature.
Since: 2.22
g_socket_get_keepalive ()
gboolean
g_socket_get_keepalive (GSocket *socket);
Gets the keepalive mode of the socket. For details on this,
see g_socket_set_keepalive().
Returns
TRUE if keepalive is active, FALSE otherwise.
Since: 2.22
g_socket_set_keepalive ()
void
g_socket_set_keepalive (GSocket *socket,
gboolean keepalive);
Sets or unsets the SO_KEEPALIVE flag on the underlying socket. When
this flag is set on a socket, the system will attempt to verify that the
remote socket endpoint is still present if a sufficiently long period of
time passes with no data being exchanged. If the system is unable to
verify the presence of the remote endpoint, it will automatically close
the connection.
This option is only functional on certain kinds of sockets. (Notably,
G_SOCKET_PROTOCOL_TCP sockets.)
The exact time between pings is system- and protocol-dependent, but will
normally be at least two hours. Most commonly, you would set this flag
on a server socket if you want to allow clients to remain idle for long
periods of time, but also want to ensure that connections are eventually
garbage-collected if clients crash or become unreachable.
Since: 2.22
g_socket_get_timeout ()
guint
g_socket_get_timeout (GSocket *socket);
Gets the timeout setting of the socket. For details on this, see
g_socket_set_timeout().
Returns
the timeout in seconds
Since: 2.26
g_socket_set_timeout ()
void
g_socket_set_timeout (GSocket *socket,
guint timeout);
Sets the time in seconds after which I/O operations on socket
will
time out if they have not yet completed.
On a blocking socket, this means that any blocking GSocket
operation will time out after timeout
seconds of inactivity,
returning G_IO_ERROR_TIMED_OUT.
On a non-blocking socket, calls to g_socket_condition_wait() will
also fail with G_IO_ERROR_TIMED_OUT after the given time. Sources
created with g_socket_create_source() will trigger after
timeout
seconds of inactivity, with the requested condition
set, at which point calling g_socket_receive(), g_socket_send(),
g_socket_check_connect_result(), etc, will fail with
G_IO_ERROR_TIMED_OUT.
If timeout
is 0 (the default), operations will never time out
on their own.
Note that if an I/O operation is interrupted by a signal, this may
cause the timeout to be reset.
Since: 2.26
g_socket_set_ttl ()
void
g_socket_set_ttl (GSocket *socket,
guint ttl);
Sets the time-to-live for outgoing unicast packets on socket
.
By default the platform-specific default value is used.
Since: 2.32
g_socket_get_ttl ()
guint
g_socket_get_ttl (GSocket *socket);
Gets the unicast time-to-live setting on socket
; see
g_socket_set_ttl() for more details.
Returns
the time-to-live setting on socket
Since: 2.32
g_socket_get_broadcast ()
gboolean
g_socket_get_broadcast (GSocket *socket);
Gets the broadcast setting on socket
; if TRUE,
it is possible to send packets to broadcast
addresses.
Returns
the broadcast setting on socket
Since: 2.32
g_socket_set_broadcast ()
void
g_socket_set_broadcast (GSocket *socket,
gboolean broadcast);
Sets whether socket
should allow sending to broadcast addresses.
This is FALSE by default.
Since: 2.32
g_socket_get_option ()
gboolean
g_socket_get_option (GSocket *socket,
gint level,
gint optname,
gint *value,
GError **error);
Gets the value of an integer-valued option on socket
, as with
getsockopt(). (If you need to fetch a non-integer-valued option,
you will need to call getsockopt() directly.)
The <gio/gnetworking.h>
header pulls in system headers that will define most of the
standard/portable socket options. For unusual socket protocols or
platform-dependent options, you may need to include additional
headers.
Note that even for socket options that are a single byte in size,
value
is still a pointer to a gint variable, not a guchar;
g_socket_get_option() will handle the conversion internally.
Returns
success or failure. On failure, error
will be set, and
the system error value (errno or WSAGetLastError()) will still
be set to the result of the getsockopt() call.
Since: 2.36
g_socket_set_option ()
gboolean
g_socket_set_option (GSocket *socket,
gint level,
gint optname,
gint value,
GError **error);
Sets the value of an integer-valued option on socket
, as with
setsockopt(). (If you need to set a non-integer-valued option,
you will need to call setsockopt() directly.)
The <gio/gnetworking.h>
header pulls in system headers that will define most of the
standard/portable socket options. For unusual socket protocols or
platform-dependent options, you may need to include additional
headers.
Returns
success or failure. On failure, error
will be set, and
the system error value (errno or WSAGetLastError()) will still
be set to the result of the setsockopt() call.
Since: 2.36
g_socket_get_family ()
GSocketFamily
g_socket_get_family (GSocket *socket);
Gets the socket family of the socket.
Since: 2.22
g_socket_get_fd ()
int
g_socket_get_fd (GSocket *socket);
Returns the underlying OS socket object. On unix this
is a socket file descriptor, and on Windows this is
a Winsock2 SOCKET handle. This may be useful for
doing platform specific or otherwise unusual operations
on the socket.
Returns
the file descriptor of the socket.
Since: 2.22
g_socket_get_local_address ()
GSocketAddress *
g_socket_get_local_address (GSocket *socket,
GError **error);
Try to get the local address of a bound socket. This is only
useful if the socket has been bound to a local address,
either explicitly or implicitly when connecting.
Returns
a GSocketAddress or NULL on error.
Free the returned object with g_object_unref().
[transfer full]
Since: 2.22
g_socket_get_protocol ()
GSocketProtocol
g_socket_get_protocol (GSocket *socket);
Gets the socket protocol id the socket was created with.
In case the protocol is unknown, -1 is returned.
Returns
a protocol id, or -1 if unknown
Since: 2.22
g_socket_get_remote_address ()
GSocketAddress *
g_socket_get_remote_address (GSocket *socket,
GError **error);
Try to get the remote address of a connected socket. This is only
useful for connection oriented sockets that have been connected.
Returns
a GSocketAddress or NULL on error.
Free the returned object with g_object_unref().
[transfer full]
Since: 2.22
g_socket_get_socket_type ()
GSocketType
g_socket_get_socket_type (GSocket *socket);
Gets the socket type of the socket.
Since: 2.22
g_socket_speaks_ipv4 ()
gboolean
g_socket_speaks_ipv4 (GSocket *socket);
Checks if a socket is capable of speaking IPv4.
IPv4 sockets are capable of speaking IPv4. On some operating systems
and under some combinations of circumstances IPv6 sockets are also
capable of speaking IPv4. See RFC 3493 section 3.7 for more
information.
No other types of sockets are currently considered as being capable
of speaking IPv4.
Returns
TRUE if this socket can be used with IPv4.
Since: 2.22
g_socket_join_multicast_group ()
gboolean
g_socket_join_multicast_group (GSocket *socket,
GInetAddress *group,
gboolean source_specific,
const gchar *iface,
GError **error);
Registers socket
to receive multicast messages sent to group
.
socket
must be a G_SOCKET_TYPE_DATAGRAM socket, and must have
been bound to an appropriate interface and port with
g_socket_bind().
If iface
is NULL, the system will automatically pick an interface
to bind to based on group
.
If source_specific
is TRUE, source-specific multicast as defined
in RFC 4604 is used. Note that on older platforms this may fail
with a G_IO_ERROR_NOT_SUPPORTED error.
To bind to a given source-specific multicast address, use
g_socket_join_multicast_group_ssm() instead.
Returns
TRUE on success, FALSE on error.
Since: 2.32
g_socket_leave_multicast_group ()
gboolean
g_socket_leave_multicast_group (GSocket *socket,
GInetAddress *group,
gboolean source_specific,
const gchar *iface,
GError **error);
Removes socket
from the multicast group defined by group
, iface
,
and source_specific
(which must all have the same values they had
when you joined the group).
socket
remains bound to its address and port, and can still receive
unicast messages after calling this.
To unbind to a given source-specific multicast address, use
g_socket_leave_multicast_group_ssm() instead.
Returns
TRUE on success, FALSE on error.
Since: 2.32
g_socket_join_multicast_group_ssm ()
gboolean
g_socket_join_multicast_group_ssm (GSocket *socket,
GInetAddress *group,
GInetAddress *source_specific,
const gchar *iface,
GError **error);
Registers socket
to receive multicast messages sent to group
.
socket
must be a G_SOCKET_TYPE_DATAGRAM socket, and must have
been bound to an appropriate interface and port with
g_socket_bind().
If iface
is NULL, the system will automatically pick an interface
to bind to based on group
.
If source_specific
is not NULL, use source-specific multicast as
defined in RFC 4604. Note that on older platforms this may fail
with a G_IO_ERROR_NOT_SUPPORTED error.
Note that this function can be called multiple times for the same
group
with different source_specific
in order to receive multicast
packets from more than one source.
Returns
TRUE on success, FALSE on error.
Since: 2.56
g_socket_leave_multicast_group_ssm ()
gboolean
g_socket_leave_multicast_group_ssm (GSocket *socket,
GInetAddress *group,
GInetAddress *source_specific,
const gchar *iface,
GError **error);
Removes socket
from the multicast group defined by group
, iface
,
and source_specific
(which must all have the same values they had
when you joined the group).
socket
remains bound to its address and port, and can still receive
unicast messages after calling this.
Returns
TRUE on success, FALSE on error.
Since: 2.56
g_socket_get_multicast_loopback ()
gboolean
g_socket_get_multicast_loopback (GSocket *socket);
Gets the multicast loopback setting on socket
; if TRUE (the
default), outgoing multicast packets will be looped back to
multicast listeners on the same host.
Returns
the multicast loopback setting on socket
Since: 2.32
g_socket_set_multicast_loopback ()
void
g_socket_set_multicast_loopback (GSocket *socket,
gboolean loopback);
Sets whether outgoing multicast packets will be received by sockets
listening on that multicast address on the same host. This is TRUE
by default.
Since: 2.32
g_socket_get_multicast_ttl ()
guint
g_socket_get_multicast_ttl (GSocket *socket);
Gets the multicast time-to-live setting on socket
; see
g_socket_set_multicast_ttl() for more details.
Returns
the multicast time-to-live setting on socket
Since: 2.32
g_socket_set_multicast_ttl ()
void
g_socket_set_multicast_ttl (GSocket *socket,
guint ttl);
Sets the time-to-live for outgoing multicast datagrams on socket
.
By default, this is 1, meaning that multicast packets will not leave
the local network.
Since: 2.32