---
name: "ffs"
section: "9"
platform: "linux"
package: "linux-manual-4.9"
version: "4.9.228-1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/ffs/9"
---

# ffs(9)

find first set bit in word

## 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.

## COPYRIGHT