SV_MAXTHREADSPERQUEUE_INFOLEVEL

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
extern (Windows) nothrow const
auto SV_MAXTHREADSPERQUEUE_INFOLEVEL = (PARMNUM_BASE_INFOLEVEL + SV_MAXTHREADSPERQUEUE_PARMNUM);

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