RtlExpandEnvironmentStrings - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_VISTA)

// private
NTSYSAPI
NTSTATUS
NTAPI
RtlExpandEnvironmentStrings(
    _In_opt_ PVOID Environment,
    _In_reads_(SourceLength) PCWSTR Source,
    _In_ SIZE_T SourceLength,
    _Out_writes_(DestinationLength) PWSTR Destination,
    _In_ SIZE_T DestinationLength,
    _Out_opt_ PSIZE_T ReturnLength
    );

#endif
#endif
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