You can use
DescribeSpotInstanceRequests to find a running Spot instance
by examining the response. If the status of the Spot instance is
the instance ID appears in the response and contains the identifier of the instance.
Alternatively, you can use DescribeInstances with a filter to look for instances
where the instance lifecycle is
Version: (assembly version)
public abstract DescribeSpotInstanceRequestsResponse DescribeSpotInstanceRequests( DescribeSpotInstanceRequestsRequest request )
Container for the necessary parameters to execute the DescribeSpotInstanceRequests service method.
Supported in: 4.5, 4.0, 3.5