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AIO_FSYNC(3) NetBSD Library Functions Manual AIO_FSYNC(3)
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aio_fsync -- asynchronous data synchronization of file (REALTIME)
POSIX Real-time Library (librt, -lrt)
aio_fsync(int op, struct aiocb *aiocbp);
The aio_fsync() system call allows the calling process to force all modi-
fied data associated with the file descriptor aiocbp->aio_fildes to be
flushed to the stable storage device. The call returns immediately after
the synchronization request has been enqueued to the descriptor; the syn-
chronization may or may not have completed at the time the call returns.
If the request could not be enqueued, generally due to invalid arguments,
the call returns without having enqueued the request.
The op argument could be set only to O_DSYNC or O_SYNC. If op is
O_DSYNC, then aio_fsync() does the same as a fdatasync() call, if O_SYNC,
then the same as fsync().
If _POSIX_PRIORITIZED_IO is defined, and the descriptor supports it, then
the enqueued operation is submitted at a priority equal to that of the
calling process minus aiocbp->aio_reqprio.
The aiocbp pointer may be subsequently used as an argument to
aio_return() and aio_error() in order to determine return or error status
for the enqueued operation while it is in progress.
The aio_fsync() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
The aio_fsync() system call will fail if:
[EAGAIN] The request was not queued because of system resource
The following conditions may be synchronously detected when the
aio_fsync() system call is made, or asynchronously, at any time there-
after. If they are detected at call time, aio_fsync() returns -1 and
sets errno appropriately; otherwise the aio_return() system call must be
called, and will return -1, and aio_error() must be called to determine
the actual value that would have been returned in errno.
[EBADF] The aiocbp->aio_fildes is invalid for writing.
[EINVAL] This implementation does not support synchronized I/O
for this file, or the op argument is neither set to
O_DSYNC nor O_SYNC.
fcntl(2), fdatasync(2), fsync(2), aio(3)
The aio_fsync() system call is expected to conform to the IEEE Std
1003.1-2001 (``POSIX.1'') standard.
The aio_fsync() system call first appeared in NetBSD 5.0.
NetBSD 9.1 May 17, 2010 NetBSD 9.1