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

/**
 * Signals or releases one object, then waits on another in one native call.
 * This is not a transaction or an atomic handoff guarantee to other threads:
 * a wait timeout or APC/alert does not roll back a completed signal operation.
 *
 * \param SignalHandle Event with EVENT_MODIFY_STATE (0x2), semaphore with
 * SEMAPHORE_MODIFY_STATE (0x2), or a mutant owned by the calling thread. No specific
 * granted access bit is required for the mutant's release, but ownership is required.
 * \param WaitHandle Waitable-object handle requiring SYNCHRONIZE (0x00100000).
 * \param Alertable TRUE permits an alert or ordinary user APC to interrupt the wait.
 * \param Timeout Optional 100-nanosecond deadline: NULL for no deadline, pointed-to
 * zero for polling, negative for a relative interval, positive for absolute NT system time.
 * \return On a completed signal, the subsequent wait's status is returned. A signal
 * failure such as STATUS_MUTANT_NOT_OWNED or STATUS_SEMAPHORE_LIMIT_EXCEEDED ends
 * the call without waiting. Other signal-object types return STATUS_OBJECT_TYPE_MISMATCH.
 * \remarks Both handles are referenced, and WaitHandle's SYNCHRONIZE access is
 * checked, before signaling on x64. An invalid or inaccessible wait
 * handle therefore does not signal the first object. Event signaling sets the event;
 * semaphore signaling increments by 1; mutant signaling releases one acquisition.
 *
 * IMPORTANT: STATUS_ABANDONED (0x80) is ambiguous in this combined call. If the
 * signal object is an abandoned mutant not owned by the caller, its release returns
 * 0x80 and the wait is never entered: no ownership of the wait object is acquired.
 * Alternatively, after a successful signal, waiting on an abandoned mutant returns
 * 0x80 and DOES acquire that wait mutant. Do not infer wait-object acquisition from
 * 0x80 without distinguishing these paths. STATUS_TIMEOUT (0x102), STATUS_USER_APC
 * (0xC0) and STATUS_ALERTED (0x101) also do not prove wait-object acquisition.
 * \sa https://learn.microsoft.com/en-us/windows/win32/api/synchapi/nf-synchapi-signalobjectandwait
 */
_Kernel_entry_
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

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

#endif
View code on GitHub