---
name: "sys_sigprocmask"
section: "9"
platform: "linux"
package: "linux-manual-3.16"
version: "3.16.56-1+deb8u1"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/sys_sigprocmask"
---

# sys\_sigprocmask(9)

examine and change blocked signals

## NAME

sys\_sigprocmask - examine and change blocked signals

## SYNOPSIS

**long sys\_sigprocmask(int** *how***, old\_sigset\_t \_\_user \*** *nset***, old\_sigset\_t \_\_user \*** *oset***);**

## ARGUMENTS

*how*

whether to add, remove, or set signals

*nset*

signals to add or remove (if non-null)

*oset*

previous value of signal mask if non-null

## DESCRIPTION

Some platforms have their own version with special arguments; others support only sys\_rt\_sigprocmask.

## COPYRIGHT