DatagramBased.conditionCheck

Checks on the readiness of datagram_based to perform operations. The operations specified in condition are checked for and masked against the currently-satisfied conditions on datagram_based. The result is returned.

[glib.types.IOCondition.In] will be set in the return value if data is available to read with [gio.datagram_based.DatagramBased.receiveMessages], or if the connection is closed remotely (EOS); and if the datagram_based has not been closed locally using some implementation-specific method (such as [gio.socket.Socket.close] or [gio.socket.Socket.shutdown] with shutdown_read set, if it’s a #GSocket).

If the connection is shut down or closed (by calling [gio.socket.Socket.close] or [gio.socket.Socket.shutdown] with shutdown_read set, if it’s a #GSocket, for example), all calls to this function will return [gio.types.IOErrorEnum.Closed].

[glib.types.IOCondition.Out] will be set if it is expected that at least one byte can be sent using [gio.datagram_based.DatagramBased.sendMessages] without blocking. It will not be set if the datagram_based has been closed locally.

[glib.types.IOCondition.Hup] will be set if the connection has been closed locally.

[glib.types.IOCondition.Err] will be set if there was an asynchronous error in transmitting data previously enqueued using [gio.datagram_based.DatagramBased.sendMessages].

Note that on Windows, it is possible for an operation to return [gio.types.IOErrorEnum.WouldBlock] even immediately after [gio.datagram_based.DatagramBased.conditionCheck] has claimed that the #GDatagramBased is ready for writing. Rather than calling [gio.datagram_based.DatagramBased.conditionCheck] and then writing to the #GDatagramBased if it succeeds, it is generally better to simply try writing right away, and try again later if the initial attempt returns [gio.types.IOErrorEnum.WouldBlock].

It is meaningless to specify [glib.types.IOCondition.Err] or [glib.types.IOCondition.Hup] in condition; these conditions will always be set in the output if they are true. Apart from these flags, the output is guaranteed to be masked by condition.

This call never blocks.