aio_return()
Get the return status for an asynchronous I/O operation
Synopsis:
#include <aio.h>
ssize_t aio_return( struct aiocb * aiocbptr );
Arguments:
- aiocbptr
- A pointer to an asynchronous I/O control block of type aiocb whose return status you want to get.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The aio_return() function returns the return status associated with the aiocb structure referenced by the aiocbptr argument. The return status for an asynchronous I/O operation is the value that's returned by the corresponding read(), write(), or fsync() operation.
You can call aio_return() exactly once to retrieve the return status of a given asynchronous operation; if you use the same aiocb structure for the same operation in a call to aio_return() or aio_error(), an error may be returned.
Returns:
The value that's returned by the corresponding read(), write(), or fsync() operation.
Errors:
- EINVAL
- The aiocbptr argument doesn't refer to an asynchronous operation whose return status hasn't yet been retrieved.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Signal handler | Yes |
| Thread | Yes |
Caveats:
The first time you call an aio_* function, a thread pool is created, making your process multithreaded if it isn't already. Because of this, after a fork() the child can not use any of the aio_*() functions if the parent used any aio_*() functions before the fork(). The thread pool isn't destroyed until your process ends.