FFLUSH(3) MachTen Programmer’s Manual FFLUSH(3)

NAME
fflush, fpurge - flush a stream

SYNOPSIS
#include <stdio.h>

int
fflush(FILE *stream)

int
fpurge(FILE *stream)

DESCRIPTION
The function fflush() forces a write of all buffered data for the given
output or update stream via the stream’s underlying write function. The
open status of the stream is unaffected.

If the stream argument is NULL, fflush() flushes all open output streams.

The function fpurge() erases any input or output buffered in the given
stream. For output streams this discards any unwritten output. For input
streams this discards any input read from the underlying object but not
yet obtained via getc(3); this includes any text pushed back via ungetc.

RETURN VALUES
Upon successful completion 0 is returned. Otherwise, EOF is returned and
the global variable errno is set to indicate the error.

ERRORS
[EBADF] Stream is not an open stream, or, in the case of fflush(), not a
stream open for writing.

The function fflush() may also fail and set errno for any of the errors
specified for the routine write(2).

SEE ALSO
write(2), fopen(3), fclose(3), setbuf(3)

STANDARDS
The fflush() function conforms to ANSI C3.159-1989 (‘‘ANSI C’’).

4.4BSD June 4, 1993 1