NtAssignProcessToJobObject - NtDoc

#ifndef _NTPSAPI_H
// Job objects
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * Assigns a process to an existing job object.
 *
 * @param JobHandle A handle to the job object to which the process will be associated. The handle must have the JOB_OBJECT_ASSIGN_PROCESS access right.
 * @param ProcessHandle A handle to the process to associate with the job object. The handle must have the PROCESS_SET_QUOTA and PROCESS_TERMINATE access rights.
 * @return NTSTATUS Successful or errant status.
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtAssignProcessToJobObject(
    _In_ HANDLE JobHandle,
    _In_ HANDLE ProcessHandle
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwAssignProcessToJobObject(
    _In_ HANDLE JobHandle,
    _In_ HANDLE ProcessHandle
    );

#endif
View code on GitHub