io_prep_fsync(3) Synchronize a file's complete in-core state with that on disk


#include <errno.h>

#include <libaio.h>

static inline void io_prep_fsync(struct iocb *iocb, int fd);

struct iocb {
void *data;
unsigned key;
short aio_lio_opcode;
short aio_reqprio;
int aio_fildes;


This is an inline convenience function for setting up an iocbv for a FSYNC request.
The file for which
iocb->aio_fildes = fd
is a descriptor is set up with the command
iocb->aio_lio_opcode = IO_CMD_FSYNC

The io_prep_fsync() function shall set up an IO_CMD_FSYNC operation to asynchronously force all I/O operations associated with the file indicated by the file descriptor aio_fildes member of the iocb structure referenced by the iocb argument and queued at the time of the call to io_submit() to the synchronized I/O completion state. The function call shall return when the synchronization request has been initiated or queued to the file or device (even when the data cannot be synchronized immediately).

All currently queued I/O operations shall be completed as if by a call to fsync(); that is, as defined for synchronized I/O file integrity completion. If the operation queued by io_prep_fsync() fails, then, as for fsync(), outstanding I/O operations are not guaranteed to have been completed.

If io_prep_fsync() succeeds, then it is only the I/O that was queued at the time of the call to io_submit() that is guaranteed to be forced to the relevant completion state. The completion of subsequent I/O on the file descriptor is not guaranteed to be completed in a synchronized fashion.

This function returns immediately. To schedule the operation, the function io_submit must be called.

Simultaneous asynchronous operations using the same iocb produce undefined results.