RtlFreeUnicodeString - NtDoc

#ifndef _NTRTL_H

NTSYSAPI
VOID
NTAPI
RtlFreeUnicodeString(
    _Inout_ _At_(UnicodeString->Buffer, _Frees_ptr_opt_) PUNICODE_STRING UnicodeString
    );

#endif
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#ifndef _NTRTL_FWD_H
// begin_forwarders
#ifndef PHNT_INLINE_FREE_FORWARDERS

//#define RtlFreeUnicodeString(UnicodeString) {if ((UnicodeString)->Buffer) RtlFreeHeap(RtlProcessHeap(), 0, (UnicodeString)->Buffer); memset(UnicodeString, 0, sizeof(UNICODE_STRING));}
FORCEINLINE
VOID
NTAPI
RtlFreeUnicodeString(
    _Inout_ _At_(UnicodeString->Buffer, _Frees_ptr_opt_) PUNICODE_STRING UnicodeString
    )
{
    if (UnicodeString->Buffer)
    {
        RtlFreeHeap(RtlProcessHeap(), 0, UnicodeString->Buffer);
        memset(UnicodeString, 0, sizeof(UNICODE_STRING));
    }
}

#endif
// end_forwarders
#endif
View code on GitHub