aio_suspend

Date:: 10-20-2011

NAME

aio_suspend - Waits for an asynchronous I/O request

SYNOPSIS

#include <aio.h>

int aio_suspend(const aiocb_t * const aiocbp[],
     int cnt, const timespec_t *timeout);

DESCRIPTION

The aio_suspend function suspends the calling thread until at least one of the asynchronous I/O operations referenced by the aiocbp argument has completed, until a signal interrupts the function, or if timeout is not NULL, until the time interval specified by timeout has passed. If any of the aiocb structures in the list correspond to the completed asynchronous I/O operations(i.e., the error status for the operation is not equal to EINPROGRESS at the time of the call), the function returns without suspending the calling thread. The aiocbp argument points to an array of pointers to asynchronous I/O control blocks. The cnt argument indicates the number of elements in the array. Each aiocb structure pointed to will have been used in initiating an asynchronous I/O request via aio_read, aio_write, or lio_listio. This array may contain NULL pointers which will be ignored. If this array contains pointers that refer to aiocb structures that have not been used in submitting asynchronous I/O, the result is undefined.

If the time interval indicated in the timespec structure pointed to by timeout passes before any of the I/O operations referenced by aiocbp are completed, then aio_suspend returns with an error.

RETURN VALUES

If the aio_suspend function returns after one or more asynchronous I/O operations has completed, zero is returned.

The application may determine which asynchronous I/O completed by scanning the associated error and return status using aio_error and aio_return, respectively.

MESSAGES

If one of the following conditions occurs, the aio_suspend function returns -1 and sets errno to the corresponding value.

EAGAIN: No asynchronous I/O indicated in the list referenced by aiocbp completed in the time interval indicated by timeout. Alternately, the system was temporarily short of resources and unable to wait for I/O.
EINTR: A signal interrupted the aio_suspend function. Note that, since each asynchronous I/O operation may possibly provoke a signal when it completes, this error return may be caused by the completion of one (or more) of the very I/O operation being awaited.