RtlFreeAnsiString - NtDoc

#ifndef _NTRTL_H

NTSYSAPI
VOID
NTAPI
RtlFreeAnsiString(
    _Inout_ _At_(AnsiString->Buffer, _Frees_ptr_opt_) PANSI_STRING AnsiString
    );

#endif
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/*
 * RTL forward symbol typedefs
 *
 * This file is part of System Informer.
 */
#ifndef _NTRTL_FWD_H
// Note: ntdll symbols and exports define these forwarders:
// begin_forwarders
#ifndef PHNT_INLINE_FREE_FORWARDERS

//#define RtlFreeAnsiString(UnicodeString) {if ((AnsiString)->Buffer) RtlFreeHeap(RtlProcessHeap(), 0, (AnsiString)->Buffer); memset(AnsiString, 0, sizeof(ANSI_STRING));}
FORCEINLINE
VOID
NTAPI
RtlFreeAnsiString(
    _Inout_ _At_(AnsiString->Buffer, _Frees_ptr_opt_) PANSI_STRING AnsiString
    )
{
    if (AnsiString->Buffer)
    {
        RtlFreeHeap(RtlProcessHeap(), 0, AnsiString->Buffer);
        memset(AnsiString, 0, sizeof(ANSI_STRING));
    }
}

#endif
// end_forwarders
#endif
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