NAME
fflush, fpurge
— flush a stream
LIBRARY
library “libc”
SYNOPSIS
#include
<stdio.h>
int
fflush(FILE
*stream);
int
fpurge(FILE
*stream);
DESCRIPTION
The functionfflush()
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(3).
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] - The stream argument is not an open stream.
The function fflush() may also fail and
set errno for any of the errors specified for the
routine write(2), except that in case of stream
being a read-only descriptor, fflush() returns
0.
SEE ALSO
STANDARDS
The fflush() function conforms to
ISO/IEC 9899:1990
(“ISO C90”).