#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * The NtQueryInstallUILanguage routine retrieves the system's installed UI language identifier.
 *
 * \param InstallUILanguageId A pointer that receives the installed UI language identifier (LANGID).
 * \return NTSTATUS Successful or errant status.
 * \see https://learn.microsoft.com/en-us/windows/win32/api/winnls/nf-winnls-getsystemdefaultuilanguage
 */
NTSYSCALLAPI
NTSTATUS
NTAPI
NtQueryInstallUILanguage(
    _Out_ LANGID *InstallUILanguageId
    );

#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQueryInstallUILanguage(
    _Out_ LANGID *InstallUILanguageId
    );

#endif
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