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

/**
 * The NtSignalAndWaitForSingleObject routine signals one object and waits on another object as a single operation.
 *
 * @param SignalHandle A handle to the object to be signaled.
 * @param WaitHandle A handle to the object to wait on. The SYNCHRONIZE access right is required.
 * @param Alertable If this parameter is TRUE, the function returns when the system queues an I/O completion routine or APC function, and the thread calls the function.
 * @param Timeout The time-out interval. The function returns if the interval elapses, even if the object's state is nonsignaled and no completion or APC objects are queued.
 * If zero, the function tests the object's state, checks for queued completion routines or APCs, and returns immediately. 
 * @return NTSTATUS Successful or errant status.
 * @sa https://learn.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-signalobjectandwait
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtSignalAndWaitForSingleObject(
    _In_ HANDLE SignalHandle,
    _In_ HANDLE WaitHandle,
    _In_ BOOLEAN Alertable,
    _In_opt_ PLARGE_INTEGER Timeout
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

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

#endif
View code on GitHub