Knowledge Hub

cleanstart-utils Reference

Version: 1.5.5 Binary: cleanstart-utils (alias: csu)

What It Does

cleanstart-utils is a BusyBox-style multi-call binary written in Rust. It provides 33 common Unix utilities in a single, memory-safe static binary for use inside CleanStart containers. Instead of installing coreutils, grep, tar, and wget separately, you get one binary that handles all of them.

Usage

Two invocation styles:

# Direct invocationcleanstart-utils cp -r /src /dstcsu grep -i "error" /var/log/app.log # Symlink invocation (zero-overhead)ln -s /usr/local/bin/cleanstart-utils /bin/cp/bin/cp -r /src /dst

When invoked with no arguments, it prints the version and lists all available applets.

Complete Applet List

Filesystem

Command	Usage	Key Flags
`cp`	`cp [-r] [-p] [-f] [-v] [-n] src... dst`	`-r` recursive, `-n` no-clobber, `-v` verbose
`mv`	`mv [-f] [-v] src... dst`	`-f` force, `-v` verbose
`rm`	`rm [-r] [-f] [-v] path...`	`-r` recursive, `-f` force
`mkdir`	`mkdir [-p] [-v] [-m MODE] dir...`	`-p` parents, `-m` mode
`chmod`	`chmod [-R] [-v] MODE path...`	`-R` recursive
`ln`	`ln [-s] [-f] [-v] target link`	`-s` symbolic, `-f` force
`touch`	`touch [-a] [-m] [-t TIME] file...`	`-t` timestamp
`cat`	`cat [-n] file...`	`-n` line numbers
`stat`	`stat [-c FMT] file...`	`-c` format string

Text Processing

Command	Usage	Key Flags
`grep`	`grep [-i] [-v] [-c] [-l] [-n] [-r] [-E] pattern [file...]`	`-i` case-insensitive, `-r` recursive, `-E` extended regex
`head`	`head [-n N] [file...]`	`-n` line count
`tail`	`tail [-n N] [-f] [file...]`	`-n` line count, `-f` follow
`wc`	`wc [-l] [-w] [-c] [file...]`	`-l` lines, `-w` words, `-c` bytes
`sort`	`sort [-r] [-n] [-u] [-k FIELD] [file...]`	`-r` reverse, `-n` numeric, `-u` unique
`uniq`	`uniq [-c] [-d] [-u] [file]`	`-c` count, `-d` duplicates only
`sed`	`sed [-i] [-e EXPR] [file...]`	`-i` in-place, `-e` expression
`echo`	`echo [-n] [-e] [string...]`	`-n` no newline, `-e` escape sequences
`printf`	`printf format [args...]`	C-style format strings

Directory and Environment

Command	Usage	Description
`ls`	`ls [-l] [-a] [-h] [-R] [path...]`	List directory contents
`pwd`	`pwd`	Print working directory
`id`	`id [-u] [-g] [-n]`	Print user/group identity
`which`	`which command`	Locate a command
`env`	`env [NAME=VALUE...] [cmd]`	Print or set environment
`printenv`	`printenv [NAME]`	Print environment variables
`date`	`date [-u] [+FORMAT]`	Print date/time
`sleep`	`sleep SECONDS`	Pause execution
`kill`	`kill [-SIGNAL] PID...`	Send signal to process
`true`	`true`	Exit 0
`false`	`false`	Exit 1

Command	Usage	Key Flags
`tar`	`tar [-c\|-x\|-t] [-z\|-J] [-f FILE] [-C DIR] [paths...]`	`-z` gzip, `-J` xz, `-C` change dir
`unzip`	`unzip [-o] [-d DIR] file.zip`	`-o` overwrite, `-d` extract dir
`gzip`	`gzip [-d] [-k] [-f] file...`	`-d` decompress, `-k` keep original
`gunzip`	`gunzip [-k] [-f] file...`	`-k` keep original

Network

Command	Usage	Key Flags
`fetch`	`fetch [-o FILE] URL`	`-o` output file
`wget`	`wget [-O FILE] [-q] URL`	`-O` output file, `-q` quiet

All network operations use TLS 1.3 via rustls (no OpenSSL dependency).

Shell

Command	Description
`sh` / `ash` / `csu-sh`	Minimal POSIX-subset shell for basic scripting

The built-in shell handles simple command execution, pipes, and redirects. Complex shell features delegate to /bin/sh if available.

Feature Flags

All features are enabled by default. When a feature is disabled at compile time, its commands return a "not compiled in" error.

Feature	Commands	Dependencies
`sed_builtin`	sed	None
`grep_builtin`	grep	regex 1.10
`archive`	tar, unzip, gzip, gunzip	tar, flate2, xz2
`net`	fetch, wget	ureq (rustls TLS 1.3)
`chrono_tools`	date (format strings)	chrono 0.4

Shared Library

cleanstart-utils also ships as libcleanstart for embedding in other tools:

use libcleanstart::{dispatch_builtin, env_expand}; // Run a builtin commanddispatch_builtin("mkdir", &["-p", "/data/logs"]); // Expand environment variableslet expanded = env_expand("$HOME/.config");

This is how cleanimg-init provides its 16 builtins -- it links against libcleanstart rather than reimplementing them.