NtOpenPrivateNamespace - NtDoc

#ifndef _NTOBAPI_H
// Private namespaces
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_VISTA)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtOpenPrivateNamespace(
    _Out_ PHANDLE NamespaceHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
    _In_ POBJECT_BOUNDARY_DESCRIPTOR BoundaryDescriptor
    );

#endif
#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwOpenPrivateNamespace(
    _Out_ PHANDLE NamespaceHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
    _In_ POBJECT_BOUNDARY_DESCRIPTOR BoundaryDescriptor
    );

#endif
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