NtQueryIoCompletion - NtDoc

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

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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Function NtQueryIoCompletion receives number of file operations pending on specified IO Completion Object.

IoCompletionHandle

HANDLE to IO Completion Object opened with IO_COMPLETION_QUERY_STATE access.

InformationClass

See IO_COMPLETION_INFORMATION_CLASS for possible values.

IoCompletionInformation

User's allocated buffer for result data.

InformationBufferLength

Length of IoCompletionInformation buffer, in bytes.

RequiredLength

Optionally receives required length of buffer.

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See also

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