#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateKeyedEvent(
    _Out_ PHANDLE KeyedEventHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
    _Reserved_ ULONG Flags
    );

#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateKeyedEvent(
    _Out_ PHANDLE KeyedEventHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
    _Reserved_ ULONG Flags
    );

#endif
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Synchronization object called KeyedEvent is available in Windows XP+ systems. It's useful when both (or more) threads have to wait for each other.

KeyedEventHandle

HANDLE to newly created KeyedEvent object.

DesiredAccess

The same values as for Event objects (typically EVENT_ALL_ACCESS).

ObjectAttributes

Optionally name of object.

Reserved

Have to be zero. Reserved for future use.

Documented by

Tomasz Nowak

NtCreateKeyedEvent - NtDoc

KeyedEventHandle

DesiredAccess

ObjectAttributes

Reserved

Documented by

See also