NAME
fflush,
fpurge —
flush a stream
LIBRARY
Standard C Library (libc, -lc)
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(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
]
- 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),
fclose(3),
fopen(3),
setbuf(3)
STANDARDS
The
fflush() function conforms to
ANSI
X3.159-1989 (“ANSI C89”).