---
name: "clear_bit"
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/clear_bit"
---

# clear\_bit(9)

Clears a bit in memory

## NAME

clear\_bit - Clears a bit in memory

## SYNOPSIS

**void clear\_bit(long** *nr***, volatile unsigned long \*** *addr***);**

## ARGUMENTS

*nr*

Bit to clear

*addr*

Address to start counting from

## DESCRIPTION

**clear\_bit** is atomic and may not be reordered. However, it does not contain a memory barrier, so if it is used for locking purposes, you should call **smp\_mb\_\_before\_atomic** and/or **smp\_mb\_\_after\_atomic** in order to ensure changes are visible on other processors.

## COPYRIGHT