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disable cout buffering

paulchen asked
Medium Priority
Last Modified: 2012-06-27
How can I disable the buffering of output from cout?

Thank you!
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cout.setf (ios::unitbuf, 0);

This forces a buffer of 1 char, which is actually no buffer at all.

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hello md!

thank you for your answer.
unfortunately, it didn't work. it still gets all buffered and
output after program termination.

I've never seen this before.  What platform/compiler?

BTW, I recall that cout is unitbuf by default.
Does "cerr" behave like you want it to (ie. unbuffered?) If it does not, then the problem could be with the OS, not the libraries you are using. (cerr is tied to fd 2 (stderr) instead of fd 1 (stdout) and is supposed to be unbuffered, though both are based the same parent class (as far as I know, may be implementation dependant)).

"clog" is supposed to be an unbuffered "cerr".
How do they do it? (tracking this doen might help)
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