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aio_fsync(2)
NAME
  aio_fsync - Asynchronously writes changes in a file to permanent storage

SYNOPSIS
  #include <aio.h>

  int aio_fsync (
	    int op,
	  struct aiocb *aiocbp );

LIBRARY
  Asynchronous I/O Library (libaio, libaio_raw)

PARAMETERS
  op  Specifies file or data synchronization.

  aiocbp
      Specifies a pointer to an aiocb structure. This function uses only the
      aio_fildes and aio_sigevent fields of the aiocbp control block.

DESCRIPTION
  The aio_fsync function asynchronously causes system buffers containing a
  file's modified data to be written to permanent storage.  All modified data
  in the file indicated by the file descriptor in the aio_fildes member of
  the aiocb structure referenced by the aiocbp argument is forced to the
  synchronized I/O completion state.

  The aio_fsync function returns when the synchronization request has been
  initiated or queued, even when data cannot be synchronized immediately.

  If op is O_DSYNC, all currently queued I/O operations are completed as if
  by a call to fdatasync. If op is O_SYNC, all currently queued I/O
  operations are completed as if by a call to fsync. If the aio_fsync
  function fails, outstanding I/O operations are not guaranteed to have been
  completed.

  If aio_fsync succeeds, only the I/O that was queued at the time of the call
  is guaranteed to be synchronized; the completion of subsequent I/O is not
  guaranteed.

  The aiocbp value may be used as an argument to the aio_error and aio_return
  functions to determine the error or return status of the asynchronous
  operation while it is proceeding. When the request is queued, the error
  status for the operation is [EINPROGRESS]. When all data has been
  synchronized, the error status is set to reflect the success or failure of
  the operation. The aio_sigevent member of the aiocb structure defines the
  signal to be generated upon completion of the operation. If
  aio_sigevent.sigev_notify equals SIGEV_SIGNAL and aio_sigevent.sigev_signo
  is non-zero, a signal will be generated when all operations have achieved
  synchronized I/O completion.

RETURN VALUES
  Upon successful completion, the aio_fsync function returns a value of 0
  (zero). If the aio_fsync function fails, a value of -1 is returned and
  errno is set to indicate the error. If aio_fsync fails, outstanding I/O
  operations are not guaranteed to have been completed.

ERRORS
  If the aio_fsync function fails, errno may be set to one of the following
  values:

  [EAGAIN]
      The requested asynchronous operation was not queued due to temporary
      resource limitations.

  [EBADF]
      The aio_fildes member of the aiocb structure is not a valid file
      descriptor.

  [EINVAL]
      A value of op other than O_DSYNC or O_SYNC was specified.

  If any queued I/O operations fail, the aio_fsync function returns error
  conditions defined for read and write. The error is returned	in the error
  status for the asynchronous fsync operation, which can be retrieved using
  aio_error.

SEE ALSO
  Functions: fdatasync(2), fcntl(2), fsync(2), open(2), read(2), sync(2),
  write(2)

  Guide to Realtime Programming

Index for Section 2

Alphabetical listing for A

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