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.
nothrow extern (Windows) const
auto SV_MAXTHREADSPERQUEUE_INFOLEVEL = (PARMNUM_BASE_INFOLEVEL + SV_MAXTHREADSPERQUEUE_PARMNUM);

Meta