RtlStringExHandleFillBehindNullW - NtDoc

#ifndef _NTSTRSAFE_H_INCLUDED_

NTSTRSAFEWORKERDDI
RtlStringExHandleFillBehindNullW(
        _Inout_updates_bytes_(cbRemaining) NTSTRSAFE_PWSTR pszDestEnd,
        _In_ size_t cbRemaining,
        _In_ DWORD dwFlags);

#endif
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#ifndef _NTSTRSAFE_H_INCLUDED_
// Below here are the worker functions that actually do the work
#if defined(NTSTRSAFE_LIB_IMPL) || !defined(NTSTRSAFE_LIB)

NTSTRSAFEWORKERDDI
    RtlStringExHandleFillBehindNullW(
            _Inout_updates_bytes_(cbRemaining) NTSTRSAFE_PWSTR pszDestEnd,
            _In_ size_t cbRemaining,
            _In_ DWORD dwFlags)
{
    if (cbRemaining > sizeof(wchar_t))
    {
        memset(pszDestEnd + 1, STRSAFE_GET_FILL_PATTERN(dwFlags), cbRemaining - sizeof(wchar_t));
    }

    return STATUS_SUCCESS;
}

#endif
#endif
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#ifndef _NTSTRSAFE_H_INCLUDED_
// Do not call these functions, they are worker functions for internal use within this file
#ifdef DEPRECATE_SUPPORTED
// ...
#else

#define RtlStringExHandleFillBehindNullW   RtlStringExHandleFillBehindNullW_do_not_call_this_function

#endif
#endif
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