ffs (9) Linux Manual Page
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.