RtlQueryEnvironmentVariable - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_VISTA)

// private
NTSYSAPI
NTSTATUS
NTAPI
RtlQueryEnvironmentVariable(
    _In_opt_ PVOID Environment,
    _In_reads_(NameLength) PCWSTR Name,
    _In_ SIZE_T NameLength,
    _Out_writes_opt_(ValueLength) PWSTR Value,
    _In_opt_ SIZE_T ValueLength,
    _Out_ PSIZE_T ReturnLength
    );

#endif
#endif
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