1 /* ffs -- Find the first bit set in the parameter
2
3 @deftypefn Supplemental int ffs (int @var{valu})
4
5 Find the first (least significant) bit set in @var{valu}. Bits are
6 numbered from right to left, starting with bit 1 (corresponding to the
7 value 1). If @var{valu} is zero, zero is returned.
8
9 @end deftypefn
10
11 */
12
13 int
ffs(valu)14 ffs (valu)
15 register int valu;
16 {
17 register int bit;
18
19 if (valu == 0)
20 return 0;
21
22 for (bit = 1; !(valu & 1); bit++)
23 valu >>= 1;
24
25 return bit;
26 }
27
28