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Flushing Buffers

Flushing output on a buffered stream means transmitting all accumulated characters to the file. There are many circumstances when buffered output on a stream is flushed automatically:

If you want to flush the buffered output at another time, call fflush, which is declared in the header file `stdio.h'.

Function: int fflush (FILE *stream)

This function causes any buffered output on stream to be delivered to the file. If stream is a null pointer, then fflush causes buffered output on all open output streams to be flushed.

This function returns EOF if a write error occurs, or zero otherwise.

Compatibility Note: Some brain-damaged operating systems have been known to be so thoroughly fixated on line-oriented input and output that flushing a line buffered stream causes a newline to be written! Fortunately, this "feature" seems to be becoming less common. You do not need to worry about this in the GNU system.

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