Class Socket

All Implemented Interfaces:
PointerInterface

public class Socket extends Object
A #GSocket is a low-level networking primitive. It is a more or less
direct mapping of the BSD socket API in a portable GObject based API.
It supports both the UNIX socket implementations and winsock2 on Windows.

#GSocket is the platform independent base upon which the higher level
network primitives are based. Applications are not typically meant to
use it directly, but rather through classes like #GSocketClient,
#GSocketService and #GSocketConnection. However there may be cases where
direct use of #GSocket is useful.

#GSocket implements the #GInitable interface, so if it is manually constructed
by e.g. g_object_new() you must call g_initable_init() and check the
results before using the object. This is done automatically in
g_socket_new() and g_socket_new_from_fd(), so these functions can return
%NULL.

Sockets operate in two general modes, blocking or non-blocking. When
in blocking mode all operations (which don’t take an explicit blocking
parameter) block until the requested operation
is finished or there is an error. In non-blocking mode all calls that
would block return immediately with a %G_IO_ERROR_WOULD_BLOCK error.
To know when a call would successfully run you can call g_socket_condition_check(),
or g_socket_condition_wait(). You can also use g_socket_create_source() and
attach it to a #GMainContext to get callbacks when I/O is possible.
Note that all sockets are always set to non blocking mode in the system, and
blocking mode is emulated in GSocket.

When working in non-blocking mode applications should always be able to
handle getting a %G_IO_ERROR_WOULD_BLOCK error even when some other
function said that I/O was possible. This can easily happen in case
of a race condition in the application, but it can also happen for other
reasons. For instance, on Windows a socket is always seen as writable
until a write returns %G_IO_ERROR_WOULD_BLOCK.

#GSockets can be either connection oriented or datagram based.
For connection oriented types you must first establish a connection by
either connecting to an address or accepting a connection from another
address. For connectionless socket types the target/source address is
specified or received in each I/O operation.

All socket file descriptors are set to be close-on-exec.

Note that creating a #GSocket causes the signal %SIGPIPE to be
ignored for the remainder of the program. If you are writing a
command-line utility that uses #GSocket, you may need to take into
account the fact that your program will not automatically be killed
if it tries to write to %stdout after it has been closed.

Like most other APIs in GLib, #GSocket is not inherently thread safe. To use
a #GSocket concurrently from multiple threads, you must implement your own
locking.

https://docs.gtk.org/gio/class.Socket.html

  • Constructor Details

    • Socket

      public Socket(PointerContainer pointer)
    • Socket

      public Socket(int family, int type, int protocol)
      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.
      Parameters:
      family - the socket family to use, e.g. %G_SOCKET_FAMILY_IPV4.
      type - the socket type to use.
      protocol - the id of the protocol to use, or 0 for default.
  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()
    • newFromFdSocket

      public static Socket newFromFdSocket(int fd) throws AllocationError
      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
      Parameters:
      fd - a native socket file descriptor.
      Returns:
      a #GSocket or %NULL on error. Free the returned object with g_object_unref().
      Throws:
      AllocationError
    • accept

      public Socket accept(@Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      cancellable - a %GCancellable or %NULL
      Returns:
      a new #GSocket, or %NULL on error. Free the returned object with g_object_unref().
      Throws:
      AllocationError
    • bind

      public boolean bind(@Nonnull SocketAddress address, boolean allow_reuse) throws AllocationError
      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.)
      Parameters:
      address - a #GSocketAddress specifying the local address.
      allow_reuse - whether to allow reusing this address
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • checkConnectResult

      public boolean checkConnectResult() throws AllocationError
      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
      Throws:
      AllocationError
    • close

      public boolean close() throws AllocationError
      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
      Throws:
      AllocationError
    • conditionCheck

      public int conditionCheck(int 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.
      Parameters:
      condition - a #GIOCondition mask to check
      Returns:
      the @GIOCondition mask of the current state
    • conditionTimedWait

      public boolean conditionTimedWait(int condition, long timeout_us, @Nullable Cancellable cancellable) throws AllocationError
      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 #GSocket: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.
      Parameters:
      condition - a #GIOCondition mask to wait for
      timeout_us - the maximum time (in microseconds) to wait, or -1
      cancellable - a #GCancellable, or %NULL
      Returns:
      %TRUE if the condition was met, %FALSE otherwise
      Throws:
      AllocationError
    • conditionWait

      public boolean conditionWait(int condition, @Nullable Cancellable cancellable) throws AllocationError
      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().
      Parameters:
      condition - a #GIOCondition mask to wait for
      cancellable - a #GCancellable, or %NULL
      Returns:
      %TRUE if the condition was met, %FALSE otherwise
      Throws:
      AllocationError
    • connect

      public boolean connect(@Nonnull SocketAddress address, @Nullable Cancellable cancellable) throws AllocationError
      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().
      Parameters:
      address - a #GSocketAddress specifying the remote address.
      cancellable - a %GCancellable or %NULL
      Returns:
      %TRUE if connected, %FALSE on error.
      Throws:
      AllocationError
    • connectionFactoryCreateConnection

      public SocketConnection connectionFactoryCreateConnection()
      Creates a #GSocketConnection subclass of the right type for
      @socket.
      Returns:
      a #GSocketConnection
    • createSource

      public Source createSource(int condition, @Nullable Cancellable 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.
      Parameters:
      condition - a #GIOCondition mask to monitor
      cancellable - a %GCancellable or %NULL
      Returns:
      a newly allocated %GSource, free with g_source_unref().
    • getAvailableBytes

      public long getAvailableBytes()
      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.
    • getBlocking

      public boolean getBlocking()
      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.
    • getBroadcast

      public boolean getBroadcast()
      Gets the broadcast setting on @socket; if %TRUE,
      it is possible to send packets to broadcast
      addresses.
      Returns:
      the broadcast setting on @socket
    • getCredentials

      public Credentials getCredentials() throws AllocationError
      Returns the credentials of the foreign process connected to this
      socket, if any (e.g. it is only supported for %G_SOCKET_FAMILY_UNIX
      sockets).

      If this operation isn't supported on the OS, the method fails with
      the %G_IO_ERROR_NOT_SUPPORTED error. On Linux this is implemented
      by reading the %SO_PEERCRED option on the underlying socket.

      This method can be expected to be available on the following platforms:

      - Linux since GLib 2.26
      - OpenBSD since GLib 2.30
      - Solaris, Illumos and OpenSolaris since GLib 2.40
      - NetBSD since GLib 2.42
      - macOS, tvOS, iOS since GLib 2.66

      Other ways to obtain credentials from a foreign peer includes the
      #GUnixCredentialsMessage type and
      g_unix_connection_send_credentials() /
      g_unix_connection_receive_credentials() functions.
      Returns:
      %NULL if @error is set, otherwise a #GCredentials object that must be freed with g_object_unref().
      Throws:
      AllocationError
    • getFamily

      public int getFamily()
      Gets the socket family of the socket.
      Returns:
      a #GSocketFamily
    • getFd

      public int getFd()
      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.
    • getKeepalive

      public boolean getKeepalive()
      Gets the keepalive mode of the socket. For details on this,
      see g_socket_set_keepalive().
      Returns:
      %TRUE if keepalive is active, %FALSE otherwise.
    • getListenBacklog

      public int getListenBacklog()
      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.
    • getLocalAddress

      public SocketAddress getLocalAddress() throws AllocationError
      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().
      Throws:
      AllocationError
    • getMulticastLoopback

      public boolean getMulticastLoopback()
      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
    • getMulticastTtl

      public int getMulticastTtl()
      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
    • getOption

      public boolean getOption(int level, int optname, @Nonnull Int value) throws AllocationError
      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>][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.
      Parameters:
      level - the "API level" of the option (eg, `SOL_SOCKET`)
      optname - the "name" of the option (eg, `SO_BROADCAST`)
      value - return location for the option value
      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.
      Throws:
      AllocationError
    • getProtocol

      public int getProtocol()
      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
    • getRemoteAddress

      public SocketAddress getRemoteAddress() throws AllocationError
      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().
      Throws:
      AllocationError
    • getSocketType

      public int getSocketType()
      Gets the socket type of the socket.
      Returns:
      a #GSocketType
    • getTimeout

      public int getTimeout()
      Gets the timeout setting of the socket. For details on this, see
      g_socket_set_timeout().
      Returns:
      the timeout in seconds
    • getTtl

      public int getTtl()
      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
    • isClosed

      public boolean isClosed()
      Checks whether a socket is closed.
      Returns:
      %TRUE if socket is closed, %FALSE otherwise
    • isConnected

      public boolean isConnected()
      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.
    • joinMulticastGroup

      public boolean joinMulticastGroup(@Nonnull InetAddress group, boolean source_specific, @Nullable Str iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to join.
      source_specific - %TRUE if source-specific multicast should be used
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • joinMulticastGroup

      public boolean joinMulticastGroup(@Nonnull InetAddress group, boolean source_specific, String iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to join.
      source_specific - %TRUE if source-specific multicast should be used
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • joinMulticastGroupSsm

      public boolean joinMulticastGroupSsm(@Nonnull InetAddress group, @Nullable InetAddress source_specific, @Nullable Str iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to join.
      source_specific - a #GInetAddress specifying the source-specific multicast address or %NULL to ignore.
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • joinMulticastGroupSsm

      public boolean joinMulticastGroupSsm(@Nonnull InetAddress group, @Nullable InetAddress source_specific, String iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to join.
      source_specific - a #GInetAddress specifying the source-specific multicast address or %NULL to ignore.
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • leaveMulticastGroup

      public boolean leaveMulticastGroup(@Nonnull InetAddress group, boolean source_specific, @Nullable Str iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to leave.
      source_specific - %TRUE if source-specific multicast was used
      iface - Interface used
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • leaveMulticastGroup

      public boolean leaveMulticastGroup(@Nonnull InetAddress group, boolean source_specific, String iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to leave.
      source_specific - %TRUE if source-specific multicast was used
      iface - Interface used
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • leaveMulticastGroupSsm

      public boolean leaveMulticastGroupSsm(@Nonnull InetAddress group, @Nullable InetAddress source_specific, @Nullable Str iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to leave.
      source_specific - a #GInetAddress specifying the source-specific multicast address or %NULL to ignore.
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • leaveMulticastGroupSsm

      public boolean leaveMulticastGroupSsm(@Nonnull InetAddress group, @Nullable InetAddress source_specific, String iface) throws AllocationError
      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.
      Parameters:
      group - a #GInetAddress specifying the group address to leave.
      source_specific - a #GInetAddress specifying the source-specific multicast address or %NULL to ignore.
      iface - Name of the interface to use, or %NULL
      Returns:
      %TRUE on success, %FALSE on error.
      Throws:
      AllocationError
    • listen

      public boolean listen() throws AllocationError
      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.
      Throws:
      AllocationError
    • receive

      public long receive(@Nonnull Str buffer, long size, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - a buffer to read data into (which should be at least @size bytes long).
      size - the number of bytes you want to read from the socket
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes read, or 0 if the connection was closed by the peer, or -1 on error
      Throws:
      AllocationError
    • receiveWithBlocking

      public long receiveWithBlocking(@Nonnull Str buffer, long size, boolean blocking, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - a buffer to read data into (which should be at least @size bytes long).
      size - the number of bytes you want to read from the socket
      blocking - whether to do blocking or non-blocking I/O
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes read, or 0 if the connection was closed by the peer, or -1 on error
      Throws:
      AllocationError
    • send

      public long send(@Nonnull Str buffer, long size, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • send

      public long send(String buffer, long size, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • sendTo

      public long sendTo(@Nullable SocketAddress address, @Nonnull Str buffer, long size, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      address - a #GSocketAddress, or %NULL
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • sendTo

      public long sendTo(@Nullable SocketAddress address, String buffer, long size, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      address - a #GSocketAddress, or %NULL
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • sendWithBlocking

      public long sendWithBlocking(@Nonnull Str buffer, long size, boolean blocking, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      blocking - whether to do blocking or non-blocking I/O
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • sendWithBlocking

      public long sendWithBlocking(String buffer, long size, boolean blocking, @Nullable Cancellable cancellable) throws AllocationError
      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.
      Parameters:
      buffer - the buffer containing the data to send.
      size - the number of bytes to send
      blocking - whether to do blocking or non-blocking I/O
      cancellable - a %GCancellable or %NULL
      Returns:
      Number of bytes written (which may be less than @size), or -1 on error
      Throws:
      AllocationError
    • setBlocking

      public void setBlocking(boolean 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.
      Parameters:
      blocking - Whether to use blocking I/O or not.
    • setBroadcast

      public void setBroadcast(boolean broadcast)
      Sets whether @socket should allow sending to broadcast addresses.
      This is %FALSE by default.
      Parameters:
      broadcast - whether @socket should allow sending to broadcast addresses
    • setKeepalive

      public void setKeepalive(boolean 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.
      Parameters:
      keepalive - Value for the keepalive flag
    • setListenBacklog

      public void setListenBacklog(int 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.
      Parameters:
      backlog - the maximum number of pending connections.
    • setMulticastLoopback

      public void setMulticastLoopback(boolean 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.
      Parameters:
      loopback - whether @socket should receive messages sent to its multicast groups from the local host
    • setMulticastTtl

      public void setMulticastTtl(int 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.
      Parameters:
      ttl - the time-to-live value for all multicast datagrams on @socket
    • setOption

      public boolean setOption(int level, int optname, int value) throws AllocationError
      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>][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.
      Parameters:
      level - the "API level" of the option (eg, `SOL_SOCKET`)
      optname - the "name" of the option (eg, `SO_BROADCAST`)
      value - the value to set the option to
      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.
      Throws:
      AllocationError
    • setTimeout

      public void setTimeout(int 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.
      Parameters:
      timeout - the timeout for @socket, in seconds, or 0 for none
    • setTtl

      public void setTtl(int ttl)
      Sets the time-to-live for outgoing unicast packets on @socket.
      By default the platform-specific default value is used.
      Parameters:
      ttl - the time-to-live value for all unicast packets on @socket
    • shutdown

      public boolean shutdown(boolean shutdown_read, boolean shutdown_write) throws AllocationError
      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.
      Parameters:
      shutdown_read - whether to shut down the read side
      shutdown_write - whether to shut down the write side
      Returns:
      %TRUE on success, %FALSE on error
      Throws:
      AllocationError
    • speaksIpv4

      public boolean speaksIpv4()
      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.
    • asDatagramBased

      public DatagramBased asDatagramBased()
      Implements interface DatagramBased. Call this to get access to interface functions.
      Returns:
      DatagramBased
    • asInitable

      public Initable asInitable()
      Implements interface Initable. Call this to get access to interface functions.
      Returns:
      Initable
    • getTypeID

      public static long getTypeID()
    • getParentTypeID

      public static long getParentTypeID()
    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()
    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()
    • getInstanceSize

      public static int getInstanceSize()