aio_cancel(3R)
NAME
aio_cancel − cancel asynchronous I/O request
SYNOPSIS
cc [ flag ... ] file ... −lposix4 [ library ... ]
#include <aio.h>
int aio_cancel(int fildes, struct aiocb ∗aiocbp
MT-LEVEL
MT-Safe
DESCRIPTION
aio_cancel() attempts to cancel either one or all outstanding asynchronous I/O requests pending on the file descriptor specified by fildes. If aiocbp is NULL, then all such outstanding cancelable requests are canceled; otherwise, the individual request referenced by aiocbp references will be canceled.
Normal completion notification occurs even for asynchronous I/O operations that are successfully canceled. If there are requests which cannot be canceled, then the normal asynchronous completion process takes place for those requests, and their associated aiocb structures are not modified.
struct aiocb {
| int | aio_fildes; | /∗ file descriptor ∗/ |
| volatile void | ∗aio_buf; | /∗ buffer location ∗/ |
| size_t | aio_nbytes; | /∗ length of transfer ∗/ |
| off_t | aio_offset; | /∗ file offset ∗/ |
| int | aio_reqprio; | /∗ request priority offset ∗/ |
| struct sigevent | aio_sigevent; | /∗ signal number and offset ∗/ |
| int | aio_lio_opcode; | /∗ listio operation ∗/ |
};
struct sigevent {
| int | sigev_notify; | /∗ notification mode ∗/ |
| int | sigev_signo; | /∗ signal number ∗/ |
| union sigval | sigev_value; | /∗ signal value ∗/ |
};
union sigval {
| int | sival_int; | /∗ integer value ∗/ |
| void | ∗sival_ptr; | /∗ pointer value ∗/ |
};
RETURN VALUES
If the requested operation(s) were canceled, aio_cancel() returns AIO_CANCELED. But if at least one of the requested operation(s) cannot be canceled because it is in progress, then AIO_NOTCANCELED is returned, and the application may determine the state of affairs for these operation(s) by using aio_error(3R). If all of the operation(s) had already completed, AIO_ALLDONE is returned. Otherwise, aio_cancel() returns -1, and sets errno to indicate the error condition.
ERRORS
EBADF fildes is not a valid file descriptor.
ENOSYS aio_cancel() is not supported by this implementation.
SEE ALSO
BUGS
In Solaris 2.4, these functions always return −1 and set errno to ENOSYS, because this release does not support the Asynchronous Input and Output option. It is our intention to provide support for these interfaces in future releases.
SunOS 5.4 — Last change: 19 Aug 1993