RtlUlonglongByteSwap - NtDoc

#ifndef _NTRTL_H
// Byte swap routines.
#ifndef PHNT_RTL_BYTESWAP

#define RtlUlonglongByteSwap(_x) _byteswap_uint64((_x))

#endif
#endif
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#ifndef _NTRTL_H
// Byte swap routines.
#ifndef PHNT_RTL_BYTESWAP
// ...
#else

NTSYSAPI
ULONGLONG
FASTCALL
RtlUlonglongByteSwap(
    _In_ ULONGLONG Source
    );

#endif
#endif
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