The consequences and pros/cons of flushing the stream in c++?

Question

I have recently read an article which stated that using `\\n` is preferable to using `std::endl` because `endl` also flushes the stream. But when I looked for a bit more information on the topic I found a site which stated: "If you are in a situation where you have to avoid buffering, you can use std::endl instead of ‘\\n’ " In which situation is it preferable not to write to the buffer? Because I only saw advantages of that technique. Isn't it also safer to write to the buffer? Because it is smaller than a hard drive it will get overwritten faster than data that is stored on the HD.

Answer 1

If you are writing the data to peripheral or external device like a printer, serial modem, internet socket, etc

where you are involved in the implementation and algorithm of the protocol, then yes flushing is a best practice.

Here is the general rule of them that solves most problem, written in the form of a rhyming poem......

" To keep the garbage from taking the lead,

always flush after each read."

IN other words, after each read operation, flush the output buffer (and vice versa)

after each write operation, flush the input buffer (and vice versa)