Standard C Library Functions aio_write(3C)
NAME
aio_write - asynchronous write to a file
SYNOPSIS
#include
int aio_write(struct aiocb *aiocbp);
DESCRIPTION
The aio_write() function allows the calling process to write
aiocbp->aio_nbytes to the file associated with
aiocbp->aio_fildes from the buffer pointed to by
aiocbp->aio_buf. The function call returns when the write
request has been initiated or, at a minimum, queued to thefile or device. If _POSIX_PRIORITIZED_IO is defined and
prioritized I/O is supported for this file, then the asyn-
chronous operation is submitted at a priority equal to the scheduling priority of the process minusaiocbp->aio_reqprio. The aiocbp may be used as an argument
to aio_error(3C) and aio_return(3C) in order to determine
the error status and return status, respectively, of the asynchronous operation while it is proceeding. The aiocbp argument points to an aiocb structure. If thebuffer pointed to by aiocbp->aio_buf or the control block
pointed to by aiocbp becomes an illegal address prior toasynchronous I/O completion, then the behavior is undefined.
If O_APPEND is not set for the file descriptor aio_fildes,
then the requested operation takes place at the absoluteposition in the file as given by aio_offset, as if lseek(2)
were called immediately prior to the operation with anoffset equal to aio_offset and a whence equal to SEEK_SET.
If O_APPEND is set for the file descriptor, write operations
append to the file in the same order as the calls were made.After a successful call to enqueue an asynchronous I/O operation, the value of the file offset for the file is unspecified.
The aiocbp->aio_sigevent structure defines what asynchronous
notification is to occur when the asynchronous operation completes, as specified in signal.h(3HEAD).The aiocbp->aio_lio_opcode field is ignored by aio_write().
SunOS 5.11 Last change: 5 Feb 2008 1
Standard C Library Functions aio_write(3C)
Simultaneous asynchronous operations using the same aiocbp produce undefined results.If _POSIX_SYNCHRONIZED_IO is defined and synchronized I/O is
enabled on the file associated with aiocbp->aio_fildes, the
behavior of this function shall be according to the defini-
tions of synchronized I/O data integrity completion and syn-
chronized I/O file integrity completion. For any system action that changes the process memory space
while an asynchronous I/O is outstanding to the address range being changed, the result of that action is undefined. For regular files, no data transfer will occur past the offset maximum established in the open file description
associated with aiocbp->aio_fildes.
RETURN VALUES
The aio_write() function returns 0 to the calling process if
the I/O operation is successfully queued; otherwise, the
function returns -1 and sets errno to indicate the error.
ERRORS
The aio_write() function will fail if:
EAGAIN The requested asynchronous I/O operation was not queued due to system resource limitations.
Each of the following conditions may be detected synchro-
nously at the time of the call to aio_write(), or asynchro-
nously. If any of the conditions below are detected synchro-
nously, the aio_write() function returns -1 and sets errno
to the corresponding value. If any of the conditions beloware detected asynchronously, the return status of the asyn-
chronous operation is set to -1, and the error status of the
asynchronous operation will be set to the corresponding value.EBADF The aiocbp->aio_fildes argument is not a valid
file descriptor open for writing.EINVAL The file offset value implied by aiocbp-
>aio_offset would be invalid, aiocbp->aio_reqprio
is not a valid value, or aiocbp->aio_nbytes is an
invalid value.SunOS 5.11 Last change: 5 Feb 2008 2
Standard C Library Functions aio_write(3C)
In the case that the aio_write() successfully queues the I/O
operation, the return status of the asynchronous operation will be one of the values normally returned by the write(2) function call. If the operation is successfully queued but is subsequently canceled or encounters an error, the error status for the asynchronous operation contains one of the values normally set by the write() function call, or one of the following:EBADF The aiocbp->aio_fildes argument is not a valid
file descriptor open for writing.EINVAL The file offset value implied by aiocbp-
>aio_offset would be invalid.
ECANCELED The requested I/O was canceled before the I/O
completed due to an explicit aio_cancel(3C)
request. The following condition may be detected synchronously or asynchronously:EFBIG The file is a regular file, aiobcp->aio_nbytes is
greater than 0 and the starting offset inaiobcp->aio_offset is at or beyond the offset max-
imum in the open file description associated withaiocbp->aio_fildes.
USAGE
The aio_write() function has a transitional interface for
64-bit file offsets. See lf64(5).
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:SunOS 5.11 Last change: 5 Feb 2008 3
Standard C Library Functions aio_write(3C)
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
| Standard | See standards(5). ||_____________________________|_____________________________|
SEE ALSO
aio_cancel(3C), aio_error(3C), aio_read(3C), aio_return(3C),
lio_listio(3C), close(2), _Exit(2), fork(2), lseek(2),
write(2), aio.h(3HEAD), signal.h(3HEAD), attributes(5), lf64(5), standards(5)SunOS 5.11 Last change: 5 Feb 2008 4