#ifndef _NTOBAPI_H
// Objects, handles
#if (PHNT_MODE != PHNT_MODE_KERNEL)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtSignalAndWaitForSingleObject(
    _In_ HANDLE SignalHandle,
    _In_ HANDLE WaitHandle,
    _In_ BOOLEAN Alertable,
    _In_opt_ PLARGE_INTEGER Timeout
    );

#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwSignalAndWaitForSingleObject(
    _In_ HANDLE SignalHandle,
    _In_ HANDLE WaitHandle,
    _In_ BOOLEAN Alertable,
    _In_opt_ PLARGE_INTEGER Timeout
    );

#endif
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Function NtSignalAndWaitForSingleObject signals one object and wait for second object. See also Win32 API SignalObjectAndWait description in Microsoft SDK.

ObjectToSignal

HANDLE to object to signal. Possible object's types are:

Event Object
Semaphore Object
Mutant Object

WaitableObject

HANDLE to object to wait for. Can be any waitable object.

Alertable

If set, APC Routine can break waiting.

Time

Optionally pointer to LARGE_INTEGER value specifying time (absolute or relative) when function time outs (in 100-ns units). Negative value means relative time.

Documented by

Tomasz Nowak