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       aio_write - asynchronous write


       #include <aio.h>

       int aio_write(struct aiocb *aiocbp);

       Link with -lrt.


       The  aio_write()  function requests an asynchronous "n = write(fd, buf,
       count)"   with   fd,   buf,   count   given   by    aiocbp->aio_fildes,
       aiocbp->aio_buf, aiocbp->aio_nbytes, respectively.  The return status n
       can be retrieved upon completion using aio_return(3).

       If O_APPEND is not set, the data is written starting  at  the  absolute
       file   offset   aiocbp->aio_offset,  regardless  of  the  current  file
       position.  If O_APPEND is set, the data is written at the  end  of  the
       file.   After  this  request, the value of the current file position is

       The "asynchronous" means that this call returns as soon as the  request
       has  been  enqueued;  the  write may or may not have completed when the
       call returns.  One tests for completion using aio_error(3).

       If _POSIX_PRIORITIZED_IO is defined, and this file  supports  it,  then
       the  asynchronous operation is submitted at a priority equal to that of
       the calling process minus aiocbp->aio_reqprio.

       The field aiocbp->aio_lio_opcode is ignored.

       No data is written to a regular file beyond its maximum offset.


       On success, 0 is returned.  On error the request is not enqueued, -1 is
       returned,  and  errno  is  set  appropriately.   If  an  error is first
       detected later, it will be reported via aio_return(3)  (returns  status
       -1)  and  aio_error(3)  (error status whatever one would have gotten in
       errno, such as EBADF).


       EAGAIN Out of resources.

       EBADF  aio_fildes is not a valid file descriptor open for writing.

       EFBIG  The file is a regular file, we want to write at least one  byte,
              but the starting position is at or beyond the maximum offset for
              this file.

       EINVAL One or more of aio_offset, aio_reqprio, aio_nbytes are  invalid.

       ENOSYS This function is not supported.




       It  is  a  good  idea  to  zero out the control block before use.  This
       control block must not be changed  while  the  write  operation  is  in
       progress.   The  buffer  area  being  written  out must not be accessed
       during the operation or undefined results may occur.  The memory  areas
       involved must remain valid.


       aio_cancel(3),  aio_error(3), aio_fsync(3), aio_read(3), aio_return(3),


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