|FFS(9)||Basic C Library Functions||FFS(9)|
ffs - find first set bit in word
int ffs(int x);
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.
|January 2017||Kernel Hackers Manual 4.8.|