---
name: "bup-demux"
section: "1"
platform: "linux"
package: "bup"
version: "0.34-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/bup-demux"
---

# bup-demux(1)

demultiplexes data and error streams from standard input

## NAME

bup-demux - demultiplexes data and error streams from standard input

## SYNOPSIS

bup demux

## DESCRIPTION

Note: this is an internal command, and may be removed or changed at any time.

`bup demux` reads standard input as a bup “multiplexed” stream of data from standard output and standard error, and reproduces that output on its own standard output and standard error. It’s primary purpose is to support [`bup-on`(1)](/bup-on/1.md).

## SEE ALSO

[`bup-on`(1)](/bup-on/1.md), [`bup-mux`(1)](/bup-mux/1.md)

## BUP

Part of the [`bup`(1)](/bup/1.md) suite.

## AUTHORS

Rob Browning ⟨rlb@defaultvalue.org⟩\\c.