Copyright Digital Equipment Corp. All rights reserved.

Return_Values

   x                  The logarithmic gamma of the x argument.
   -HUGE_VAL          The x argument is a negative integer; errno is
                      set to ERANGE.
   NaN                The x argument is NaN; errno is set to EDOM.
   0                  Underflow occurred; errno is set to ERANGE.
   HUGE_VAL           Overflow occurred; errno is set to ERANGE.