RtlConvertLCIDToString - NtDoc

#ifndef _NTRTL_H
// Locale
#if (PHNT_VERSION >= PHNT_VISTA)

// private
NTSYSAPI
NTSTATUS
NTAPI
RtlConvertLCIDToString(
    _In_ LCID LcidValue,
    _In_ ULONG Base,
    _In_ ULONG Padding, // string is padded to this width
    _Out_writes_(Size) PWSTR pResultBuf,
    _In_ ULONG Size
    );

#endif
#endif
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