IO_STATUS_BLOCK - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers 
#ifndef _NTIOAPI_H

typedef struct _IO_STATUS_BLOCK
{
    union
    {
        NTSTATUS Status;
        PVOID Pointer;
    };
    ULONG_PTR Information;
} IO_STATUS_BLOCK, *PIO_STATUS_BLOCK;

#endif

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This structure is documented in Windows Driver Kit.

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