PTRDIFF_T_MAX - NtDoc

#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)
#ifdef _WIN64

#define PTRDIFF_T_MAX   9223372036854775807i64

#endif
#endif
#endif
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#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)
#ifdef _WIN64
// ...
#else

#define PTRDIFF_T_MAX   2147483647

#endif
#endif
#endif
View code on GitHub