SI_PAD

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
  1. auto SI_PAD;
    version(!linux && !OSX && !FreeBSD && solaris)
    extern (C) const
    static if(size_t.sizeof == 8)
    auto SI_PAD = ((SI_MAXSZ / int.sizeof) - 4);
  2. auto SI_PAD;

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