Name

ffs — find first set bit in word

Synopsis

int ffs (int  x);

Arguments

x

the word to search

Description

This is defined the same way as the libc and compiler builtin ffs routines, therefore differs in spirit from the other bitops.

ffs(value) returns 0 if value is 0 or the position of the first set bit if value is nonzero. The first (least significant) bit is at position 1.