What is exact meaning of iostream is sync with ios_base::sync_with_stdio

c, c++, iostream, stdout

Solution

The default ostream used by std::cout and stdio(like printf) is stdout, but it is not necessarily so.

The output could alway be redirected to the other destination. Referencing this: http://www.tldp.org/LDP/abs/html/io-redirection.html

Problem

Is this simply means whatever we do with object like cout gets in sync with stdout (and vice versa?). What does this exactly mean. Is stdio also sync with stdout?

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