aio_write - asynchronous write
int aio_write(struct aiocb *
The aio_write() function queues the I/O request described by the buffer pointed to by
aiocbp. This function is the asynchronous analog of write(2). The arguments of the call
write(fd, buf, count)
correspond (in order) to the fields
aio_nbytes of the structure pointed to by
aiocbp. (See aio(7) for a description of the
If O_APPEND is not set, the data is written starting at the absolute position
aiocbp->aio_offset, regardless of the file offset. If O_APPEND is set, data is written at the end of the file in the same order as aio_write() calls are made. After the call, the value of the file offset is unspecified.
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). The return status of a completed I/O operation can be obtained aio_return(3). Asynchronous notification of I/O completion can be obtained by setting
aiocbp->aio_sigevent appropriately; see sigevent(7) for details.
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_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 detected only 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).
Out of resources.
aio_fildes is not a valid file descriptor open for writing.
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.
One or more of
aio_nbytes are invalid.
aio_write() is not implemented.
For an explanation of the terms used in this section, see attributes(7).
It is a good idea to zero out the control block before use. The 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.
Simultaneous I/O operations specifying the same
aiocb structure produce undefined results.
aio_cancel(3), aio_error(3), aio_fsync(3), aio_read(3), aio_return(3), aio_suspend(3), lio_listio(3), aio(7)
This page is part of release 5.10 of the Linux
man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.