---
name: "snd_ctl_add_slave"
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/snd_ctl_add_slave"
---

# snd\_ctl\_add\_slave(9)

Add a virtual slave control

## NAME

snd\_ctl\_add\_slave - Add a virtual slave control

## SYNOPSIS

**int snd\_ctl\_add\_slave(struct snd\_kcontrol \*** *master***, struct snd\_kcontrol \*** *slave***);**

## ARGUMENTS

*master*

vmaster element

*slave*

slave element to add

## DESCRIPTION

Add a virtual slave control to the given master element created via **snd\_ctl\_create\_virtual\_master** beforehand.

All slaves must be the same type (returning the same information via info callback). The function doesn't check it, so it's your responsibility.

Also, some additional limitations: at most two channels, logarithmic volume control (dB level) thus no linear volume, master can only attenuate the volume without gain

## RETURN

Zero if successful or a negative error code.

## COPYRIGHT