FFLUSH(3) | Library Functions Manual | FFLUSH(3) |
fflush
, fpurge
— flush a stream
#include
<stdio.h>
int
fflush
(FILE
*stream);
int
fpurge
(FILE
*stream);
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(3).
Upon successful completion 0 is returned. Otherwise,
EOF
is returned and the global variable
errno is set to indicate the error.
EBADF
]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).
The fflush
() function conforms to
ANSI X3.159-1989
(“ANSI C89”).
A predecessor flush
() first appeared in
Version 1 AT&T UNIX. The
fflush
() function first appeared in
Version 4 AT&T UNIX.
September 7, 2019 | OpenBSD-current |