#ifndef _NTIOAPI_H

/**
 * The NtQueryIoCompletion routine queries information about an I/O completion port.
 *
 * \param[in] IoCompletionHandle Handle to the I/O completion port.
 * \param[in] IoCompletionInformationClass The type of information to query.
 * \param[out] IoCompletionInformation Pointer to a buffer that receives the information.
 * \param[in] IoCompletionInformationLength The size of the buffer.
 * \param[out, optional] ReturnLength Pointer to a variable that receives the number of bytes returned.
 * \return NTSTATUS Successful or errant status.
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtQueryIoCompletion(
    _In_ HANDLE IoCompletionHandle,
    _In_ IO_COMPLETION_INFORMATION_CLASS IoCompletionInformationClass,
    _Out_writes_bytes_(IoCompletionInformationLength) PVOID IoCompletionInformation,
    _In_ ULONG IoCompletionInformationLength,
    _Out_opt_ PULONG ReturnLength
    );

#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQueryIoCompletion(
    _In_ HANDLE IoCompletionHandle,
    _In_ IO_COMPLETION_INFORMATION_CLASS IoCompletionInformationClass,
    _Out_writes_bytes_(IoCompletionInformationLength) PVOID IoCompletionInformation,
    _In_ ULONG IoCompletionInformationLength,
    _Out_opt_ PULONG ReturnLength
    );

#endif
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