Asked by: Firmino Frizzi
technology and computing databases

What is an event loop in programming?

Last Updated: 28th February, 2020

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event loop. A programming structure thatcontinually tests for external events and calls theappropriate routines to handle them. An event loop is oftenthe main loop in a program that typically waits forthe user to trigger something.

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Subsequently, one may also ask, how does the event loop work?

The Event Loop has one simple job —to monitor the Call Stack and the Callback Queue. If the Call Stackis empty, it will take the first event from the queue andwill push it to the Call Stack, which effectively runs it. Such aniteration is called a tick in the Event Loop. Eachevent is just a function callback.

Likewise, how does Nodejs event loop work? All Node JS applications uses “SingleThreaded Event Loop Model” architecture to handlemultiple concurrent clients. The main event loop issingle-threaded but most of the I/O works run on separatethreads, because the I/O APIs in Node.js areasynchronous/non-blocking by design, in order to accommodate theevent loop.

what is an event loop Python?

An event loop is a loop that can registertasks to be executed, execute them, delay or even cancel them andhandle different events related to these operations.Generally, we schedule multiple async functions to the eventloop. The loop runs one function, while that functionwaits for IO, it pauses it and runs another.

What is setImmediate?

Understanding setImmediate() Any function passed as the setImmediate()argument is a callback that's executed in the next iteration of theevent loop. A function passed to process.nextTick() is going to beexecuted on the current iteration of the event loop, after thecurrent operation ends.

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