RtlStringCchCopyW - NtDoc

#ifndef _NTSTRSAFE_H_INCLUDED_
#ifndef NTSTRSAFE_LIB_IMPL
#ifndef NTSTRSAFE_NO_CCH_FUNCTIONS

NTSTRSAFEDDI
    RtlStringCchCopyW(
            _Out_writes_(cchDest) _Always_(_Post_z_) NTSTRSAFE_PWSTR pszDest,
            _In_ size_t cchDest,
            _In_ NTSTRSAFE_PCWSTR pszSrc)
{
    NTSTATUS status;

    status = RtlStringValidateDestW(pszDest, cchDest, NTSTRSAFE_MAX_CCH);

    if (NT_SUCCESS(status))
    {
        status = RtlStringCopyWorkerW(pszDest,
                cchDest,
                NULL,
                pszSrc,
                NTSTRSAFE_MAX_LENGTH);
    }
    else if (cchDest > 0)
    {
        *pszDest = L'\0';
    }

    return status;
}

#endif
#endif
#endif
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