промыть ручей (flush a stream)
Имя (Name)
fflush - flush a stream
Синопсис (Synopsis)
#include <stdio.h>
int fflush(FILE *stream);
Описание (Description)
For output streams, fflush() forces a write of all user-space
buffered data for the given output or update stream via the
stream's underlying write function.
For input streams associated with seekable files (e.g., disk
files, but not pipes or terminals), fflush() discards any
buffered data that has been fetched from the underlying file, but
has not been consumed by the application.
The open status of the stream is unaffected.
If the stream argument is NULL, fflush() flushes all open output
streams.
For a nonlocking counterpart, see unlocked_stdio(3).
Возвращаемое значение (Return value)
Upon successful completion 0 is returned. Otherwise, EOF is
returned and errno is set to indicate the error.
Ошибки (Error)
EBADF stream is not an open stream, or is not open for writing.
The function fflush() may also fail and set errno for any of the
errors specified for write(2).
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├──────────────────────────────────────┼───────────────┼─────────┤
│fflush() │ Thread safety │ MT-Safe │
└──────────────────────────────────────┴───────────────┴─────────┘
Стандарты (Conforming to)
C89, C99, POSIX.1-2001, POSIX.1-2008.
POSIX.1-2001 did not specify the behavior for flushing of input
streams, but the behavior is specified in POSIX.1-2008.
Примечание (Note)
Note that fflush() flushes only the user-space buffers provided
by the C library. To ensure that the data is physically stored
on disk the kernel buffers must be flushed too, for example, with
sync(2) or fsync(2).
Смотри также (See also)
fsync(2), sync(2), write(2), fclose(3), fileno(3), fopen(3),
fpurge(3), setbuf(3), unlocked_stdio(3)
