ash

Lightweight POSIX-compliant shell

TLDR

Start ash shell

$ ash

Execute a command

$ ash -c "[command]"

Run script

$ ash [script.sh]

SYNOPSIS

ash [-c command] [script] [arguments]

ash (Almquist Shell) is a lightweight POSIX-compliant shell. It's smaller and faster than bash, making it suitable for embedded systems and as /bin/sh on minimal systems.Many systems use dash (Debian Almquist Shell) as their ash implementation. BusyBox also includes an ash implementation.

PARAMETERS

-c command

Execute command string

-i

Interactive mode

-l

Login shell

-s

Read commands from stdin

-e

Exit immediately if a command exits with a non-zero status (errexit).

-x

Print each command to stderr before executing it (xtrace).

CONFIGURATION

/etc/profile

System-wide login shell initialization.

~/.profile

Per-user login shell initialization.

$ENV

If set, sourced for interactive shells (often points to ~/.ashrc).

CAVEATS

Less feature-rich than bash; no arrays, extended globbing, or many bashisms. Scripts should use POSIX syntax only. Good for speed, not convenience.

HISTORY

ash was written by Kenneth Almquist for BSD Unix in 1989 as a POSIX-compliant replacement for the Bourne shell. It has been forked into dash and is used in BusyBox.

ash