int
fflush(
FILE *stream
)
int
fpurge(
FILE *stream
)
)
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).
EOF
is returned and the global variable
errno
is set to indicate the error.
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).
)
function
conforms to
ANSI X3.159-1989 (``ANSI C89'') .