Controls stream buffering and buffer size.

#include <stdio.h>

int setvbuf (FILE *stream, char *buffer, int mode, size_t size);

Parameters

stream

Pointer to FILE structure; must refer to an open stream file that has not been read from or written to since it was opened.

buffer

Pointer to a user-allocated character array used for buffering. If a null pointer references buffer, a buffer of size bytes is automatically allocated.

mode

Buffering mode.

_IOFBF	Full buffering; that is, buffer is used as the buffer and size is used as the size of the buffer.
_IONBF	No buffer is used, regardless of buffer or size.

size

Size of buffer. Legal values are greater than 0 and less than INT_MAX.

Return Values

0 (zero).

Success.

Any other valure; an illegal type or buffer size was specified.

Failure.

Requirements

See Also

fclose, setbuf