Description
Low-level socket objectMethods and Functions
gSocketNew(family, type, protocol, .errwarn = TRUE)
gSocketNewFromFd(fd, .errwarn = TRUE)
gSocketBind(object, address, allow.reuse, .errwarn = TRUE)
gSocketListen(object, .errwarn = TRUE)
gSocketAccept(object, cancellable = NULL, .errwarn = TRUE)
gSocketConnect(object, address, cancellable = NULL, .errwarn = TRUE)
gSocketCheckConnectResult(object, .errwarn = TRUE)
gSocketReceive(object, size, cancellable = NULL, .errwarn = TRUE)
gSocketReceiveFrom(object, size, cancellable = NULL, .errwarn = TRUE)
gSocketReceiveMessage(object, flags = 0, cancellable = NULL, .errwarn = TRUE)
gSocketSend(object, buffer, size, cancellable = NULL, .errwarn = TRUE)
gSocketSendTo(object, address, buffer, size, cancellable = NULL, .errwarn = TRUE)
gSocketSendMessage(object, address, vectors, messages = NULL, flags = 0, cancellable = NULL, .errwarn = TRUE)
gSocketClose(object, .errwarn = TRUE)
gSocketIsClosed(object)
gSocketShutdown(object, shutdown.read, shutdown.write, .errwarn = TRUE)
gSocketIsConnected(object)
gSocketCreateSource(object, condition, cancellable = NULL)
gSocketConditionCheck(object, condition)
gSocketConditionWait(object, condition, cancellable = NULL, .errwarn = TRUE)
gSocketSetListenBacklog(object, backlog)
gSocketGetListenBacklog(object)
gSocketGetBlocking(object)
gSocketSetBlocking(object, blocking)
gSocketGetKeepalive(object)
gSocketSetKeepalive(object, keepalive)
gSocketGetFamily(object)
gSocketGetFd(object)
gSocketGetLocalAddress(object, .errwarn = TRUE)
gSocketGetProtocol(object)
gSocketGetRemoteAddress(object, .errwarn = TRUE)
gSocketGetSocketType(object)
gSocketSpeaksIpv4(object)
gSocket(family, type, protocol, .errwarn = TRUE)
Hierarchy
GObject
+----GSocketDetailed Description
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. gObjectNew
you must call gInitableInit
and check the
results before using the object. This is done automatically in
gSocketNew
and gSocketNewFromFd
, so these functions can return
NULL
.
Sockets operate in two general modes, blocking or non-blocking. When
in blocking mode all operations 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 gSocketConditionCheck
,
or gSocketConditionWait
. You can also use gSocketCreateSource
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
.
GSocket
s 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.Convenient Construction
gSocket
is the equivalent of gSocketNew
.References
http://library.gnome.org/devel//gio/GSocket.html