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

/**
 * Retrieves the context of the specified thread.
 *
 * \param ThreadHandle A handle to the thread.
 * \param ThreadContext A pointer to a CONTEXT structure that receives the thread context.
 * \return NTSTATUS Successful or errant status.
 * \remarks Requires THREAD_GET_CONTEXT (0x8); ContextFlags selects the register groups. The context representation and
 * alignment depend on the architecture, with a distinct Wow64NtGetContextThread path for 32-bit callers. A
 * live running thread context is not a stable snapshot; synchronize or suspend an owned target before
 * inspecting execution state.
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtGetContextThread(
    _In_ HANDLE ThreadHandle,
    _Inout_ PCONTEXT ThreadContext
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwGetContextThread(
    _In_ HANDLE ThreadHandle,
    _Inout_ PCONTEXT ThreadContext
    );

#endif
View code on GitHub