NtWaitForKeyedEvent - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers 
#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtWaitForKeyedEvent(
    _In_opt_ HANDLE KeyedEventHandle,
    _In_ PVOID KeyValue,
    _In_ BOOLEAN Alertable,
    _In_opt_ PLARGE_INTEGER Timeout
    );

#endif
#endif

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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwWaitForKeyedEvent(
    _In_opt_ HANDLE KeyedEventHandle,
    _In_ PVOID KeyValue,
    _In_ BOOLEAN Alertable,
    _In_opt_ PLARGE_INTEGER Timeout
    );

#endif

View code on GitHub

Function with similar functionality as NtReleaseKeyedEvent. In my opinion it is not needed and exists only for future vision of KeyedEvent objects or just as a mistake.

KeyedEventHandle

HANDLE for previously opened KeyedEvent object.

Key

Value to wait for, must have lowest bit clear.

Alertable

If set, waiting can be broken by alerting thread.

Timeout

Optionally pointer for timing out value.

Documented by

See also

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