Example for aio_error and aio_return Functions
The following example illustrates how the
aio_error()
and
aio_return()
functions can be used.
int aio_ex_3(HANDLE fd)
{
static struct aiocb aio;
static struct aiocb *aio_list[] = {&aio};
int ret;
char *dat = "Hello from Ex-3\n";
/* Data initialization and asynchronously writing */
IC_AIO_DATA_INIT(aio, fd, dat, strlen(dat), 0);
if (aio_write(& aio) == -1) return errno;
ret = aio_error(&aio);
if ( ret == EINPROGRESS ) {
fprintf(stderr, "ERRNO=%d STR=%s\n", ret, strerror(ret));
ret = aio_suspend(aio_list, 1, NULL);
if (ret == -1) return errno;}
else if (ret)
return ret;
ret = aio_error(&aio);
if (ret) return ret;
ret = aio_return(&aio);
printf("ret=%d\n", ret);
return 0;
}/* aio_ex_3 */Result upon execution:
-bash-3.00$ ./a.out
ERRNO=115 STR=Operation now in progress
ret=16
-bash-3.00$ cat dat
Hello from Ex-3Remarks:
- In the example, theIC_AIO_DATA_INITis defined as follows:#define IC_AIO_DATA_INIT(_aio, _fd, _dat, _len, _off)\ {memset(&_aio, 0, sizeof(_aio)); \ _aio.aio_fildes = _fd; \ _aio.aio_buf = _dat; \ _aio.aio_nbytes = _len; \ _aio.aio_offset = _off;}
- The file descriptorfdis obtained as:HANDLE fd = CreateFile("dat", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL/*|FILE_FLAG_OVERLAPPED*/, NULL);