aio_cancel - cancel an outstanding asynchronous I/O request
#include <aio.h>
int aio_cancel(int fd , struct aiocb * aiocbp );
The aio_cancel () function attempts to cancel outstanding asynchronous I/O requests for the file descriptor fd . If aiocbp is NULL, all such requests are canceled. Otherwise, only the request described by the control block pointed to by aiocbp is canceled.
Normal asynchronous notification occurs for canceled requests. The request return status is set to -1, and the request error status is set to ECANCELED . The control block of requests that cannot be canceled is not changed.
If aiocbp is not NULL, and fd differs from the file descriptor with which the asynchronous operation was initiated, unspecified results occur.
Which operations are cancellable is implementation-defined.
This function returns AIO_CANCELED if all requests were successfully canceled. It returns AIO_NOTCANCELED when at least one of the requests specified was not canceled because it was in progress. In this case one may check the status of individual requests using aio_error (3). This function returns AIO_ALLDONE when all requests had been completed already before this call. When some error occurs, -1 is returned, and errno is set appropriately.
EBADF fd is not a valid file descriptor.
aio_error (3) aio_fsync (3) aio_read (3) aio_return (3) aio_suspend (3) aio_write (3)
