#ifndef _NTPSAPI_H
//
// Threads
//
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * The NtAlertThread routine alerts the specified thread.
 *
 * \param[in] ThreadHandle A handle to the thread to be alerted.
 * \return NTSTATUS Successful or errant status.
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtAlertThread(
    _In_ HANDLE ThreadHandle
    );

#endif
#endif
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#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwAlertThread(
    _In_ HANDLE ThreadHandle
    );

#endif
View code on GitHub

NtDoc

Alerts and wakes the specified thread that previously entered an alertable wait, causing it to return STATUS_ALERTED.

Parameters

ThreadHandle - a handle to a thread granting THREAD_ALERT access.

Remarks

Despite the name similarity, this function is unrelated to NtAlertThreadByThreadId.

Related Win32 API

This functionality is not exposed in Win32 API.

NTinternals.net (undocumented.ntinternals.net)

ThreadHandle

Handle to opened Thread Object.

NtAlertThread puts specified thread in alerted state.

Documented by

ReactOS
Tomasz Nowak

NtAlertThread - NtDoc