MULDIV(3)                                               MULDIV(3)

          muldiv, umuldiv - high-precision multiplication and division

          #include <u.h>
          #include <libc.h>

          long  muldiv(long a, long b, long c)

          ulong umuldiv(ulong a, ulong b, ulong c)

          Muldiv returns a*b/c, using a vlong to hold the intermediate
          result.  Umuldiv is the equivalent for unsigned integers.
          They can be used to scale integer values without worry about
          overflowing the intermediate result.

          On some architectures, these routines can generate a trap if
          the final result does not fit in a long or ulong; on others
          they will silently truncate.