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added in API level 23

MessageQueue.OnFileDescriptorEventListener

public static interface MessageQueue.OnFileDescriptorEventListener

android.os.MessageQueue.OnFileDescriptorEventListener


A listener which is invoked when file descriptor related events occur.

Summary

Constants

int EVENT_ERROR

File descriptor event: Indicates that the file descriptor encountered a fatal error.

int EVENT_INPUT

File descriptor event: Indicates that the file descriptor is ready for input operations, such as reading.

int EVENT_OUTPUT

File descriptor event: Indicates that the file descriptor is ready for output operations, such as writing.

Public methods

abstract int onFileDescriptorEvents(FileDescriptor fd, int events)

Called when a file descriptor receives events.

Constants

EVENT_ERROR

added in API level 23
public static final int EVENT_ERROR

File descriptor event: Indicates that the file descriptor encountered a fatal error.

File descriptor errors can occur for various reasons. One common error is when the remote peer of a socket or pipe closes its end of the connection.

This event may be generated at any time regardless of whether the EVENT_ERROR event mask was specified when the listener was added.

Constant Value: 4 (0x00000004)

EVENT_INPUT

added in API level 23
public static final int EVENT_INPUT

File descriptor event: Indicates that the file descriptor is ready for input operations, such as reading.

The listener should read all available data from the file descriptor then return true to keep the listener active or false to remove the listener.

In the case of a socket, this event may be generated to indicate that there is at least one incoming connection that the listener should accept.

This event will only be generated if the EVENT_INPUT event mask was specified when the listener was added.

Constant Value: 1 (0x00000001)

EVENT_OUTPUT

added in API level 23
public static final int EVENT_OUTPUT

File descriptor event: Indicates that the file descriptor is ready for output operations, such as writing.

The listener should write as much data as it needs. If it could not write everything at once, then it should return true to keep the listener active. Otherwise, it should return false to remove the listener then re-register it later when it needs to write something else.

This event will only be generated if the EVENT_OUTPUT event mask was specified when the listener was added.

Constant Value: 2 (0x00000002)

Public methods

onFileDescriptorEvents

added in API level 23
public abstract int onFileDescriptorEvents (FileDescriptor fd, 
                int events)

Called when a file descriptor receives events.

Parameters
fd FileDescriptor: The file descriptor.

This value must never be null.

events int: The set of events that occurred: a combination of the EVENT_INPUT, EVENT_OUTPUT, and EVENT_ERROR event masks.

Value is either 0 or combination of EVENT_INPUT, EVENT_OUTPUT or EVENT_ERROR.

Returns
int The new set of events to watch, or 0 to unregister the listener.

Value is either 0 or combination of EVENT_INPUT, EVENT_OUTPUT or EVENT_ERROR.