Node.js Writable Stream unpipe Event

The 'unpipe' event in a Writable Stream is emitted when the stream.unpipe() method is being called on a Readable stream by detaching this Writable from its set of destinations. 

Syntax:

 Event: 'unpipe'

Return Value: If the unpipe() method is being called then this event is emitted else it's not emitted. 

The below examples illustrate the use of the 'unpipe' event in Node.js: 

Example 1: 

Output:

Unpiped!
Program Ended...

Example 2: 

Output:

Program Ended...

So, here unpipe() function is not called so the unpipe event is not emitted. 

Reference: https://nodejs.org/api/stream.html#stream_event_unpipe