# Ifevent : Network interface event

This module provides network interface event listening service.

User can use the following code to import the Ifevent module.

var Ifevent = require('router/ifevent');

# Support

The following shows Ifevent module APIs available for each permissions.

# Ifevent Class

# new Ifevent()

• Returns: {Object} Returns ifevent object.

Create a network interface event listener.

# Example

var ifevent = new Ifevent();

# Ifevent.open()

• Returns: {Object} Returns ifevent object.

Same as new Ifevent(), but returns undefined with no exception.

# Ifevent Object

The ifevent object inherits from EventEmitter, and the on() method can be used to add processing callbacks for different events.

# ifevent.close()

Close this ifevent and reclaiming file descriptors. Due to the addition of asynchronous events, you must call this function manually when this object is no longer used.

# ifevent.on(event, fn)

• event {Integer} Network interface event.
• fn {Function} Network interface event callback.
  • ifname {String} Network interface.

Add response functions for different network interface events.

event contains the following types of events:

• Common event:

• Point-to-point network event:

# Example

var ifevent = Ifevent.open();
ifevent.on(Ifevent.IF_AUTH_FAIL, function(ifname) {
  console.log('Interface:', ifname, 'authentication failed!');
});
iosched.forever();

# ifevent.on(ifname, fn)

• ifname {String} Network interface.
• fn {Function} Network interface event callback.
  • event {Integer} Network interface event.

Add response functions for one network interface's all events.

# Example

var ifevent = Ifevent.open();
ifevent.on('en1', function(event) {
  // Network interface: en1 has a event.
});

# ifevent.on('all', fn)

• 'all' {String} All events.
• fn {Function} Network interface event callback.
  • ifname {String} Network interface.
  • event {Integer} Network interface event.

# Example

var ifevent = Ifevent.open();
ifevent.on('all', function(ifname, event) {
  // Network interface: ifname has a event.
});

# ifevent.on('error', fn)

• 'error' {String} An error occured.
• fn {Function} Network interface event callback.
  • error {Error} error information.

If an error occured an error event is emitted with the error information. System will automatically call ifevent.close() later.

# Example

var ifevent = Ifevent.open();
ifevent.on('error', function(error)) {
  // check error information
}

# ifevent.clear()

Clear all unreceived event information.

# Example

var ifevent = Ifevent.open();
ifevent.clear();