Unwrap

Wrapper to marry GNU Parallel and 7-Zip for archive extraction.

• Author: Tuncay D.
• Source: Github
• License: MIT

What is this script for?

It uses 7z to extract files from archives. By also utilizing GNU Parallel, multiple archives can be processed at the same time.

Purpose is to streamline option handling and usability of both programs into an unified interface. Sensible defaults and only functionality I care about are incorporated. 7z option and argument handling is confusing, doing things in unconventional ways. On the other side, we have Parallel, which is complicated and has ton of features; also confusing. So I picked up my favorite options and bundled them into a manageable script.

Name of the script is inspired by unwrap() operation from Rust programming language. It's purpose is to provide the content of certain type of variables, by looking inside of it and taking it out.

Installation

This is a Bash script. It does not need an installation. Just download and give it the executable bit.

Requirements

Linux only. 2 programs are required as a dependency:

• parallel: GNU Parallel
• 7z: p7zip (fork from 7z)

These applications are provided by packages that may have been packaged differently, depending on the distribution or package manager. Here is a list of commands with known setups to install:

Arch (includes Manjaro, EndeavourOS)

pacman -S parallel p7zip

Download

There is no release or build version of the script. Just get the source, make the script executable and put the file in a folder that is found in the $PATH variable.

git clone https://github.com/thingsiplay/unwrap
cd unwrap
chmod +x unwrap

Copy / Install

Following install operation is optional and is just an example how you could copy the script to your system. Use a destination that makes sense for your system (i.e. a directory where executable files are located).

\install -v unwrap ~/.local/bin/

Note: The backslash at the beginning of \install tells Bash to ignore Bash alias or functions and use the program directly.

How to use

I won't go too much into detail here, as the script has a descriptive help page: unwrap -h , or more explanation with unwrap -H

Without options, dedicated sub folders for each archive file to unpack under are created automatically. Following command will take my_1.zip archive and unpack it's content under a dedicated folder my_1/ in the same directory. Existing files in that folder will not be overwritten by files with same name from archive content.

unwrap my_1.zip

When multiple files are given, then 2 files will be processed at the same time with parallel:

unwrap *.zip

Use option -a to overwrite existing files:

unwrap -a *.zip

Only supported files are processed, such as .7z, .zip and more. This allows us to just give over any file. The script will workout what it can unpack and which to skip based on it's file extension:

unwrap -a *

Option -A will disable automatic extension check and instruct to process all files:

unwrap -a -A *

Some files can start with a dash - character in the name, which could potentially be interpreted as an option for the script. Use a double dash -- to indicate that anything after that is a file and not an option:

unwrap -a -A -- -my_unusual_file.zip

With -i GLOB a file name or path with wildcards can be specified, to extract only files that match the GLOB pattern. Option -f will ignore archives internal sub directory structure and extract a flat structure only. -o DIR will specify a directory to channel all extracted files and folders into.

Let's combine all these three options to extract .txt files into current working dir. Dedicated sub folders for each archives are still created by default, to separate the extraction:

unwrap -f -i '*.txt' -o . *.zip

Or same as above, but shorter:

unwrap -fi*.txt -o. *.zip

There are a few more options available. You can also instruct the script to not execute any 7z command, but instead list them for inspection. Just add -X to it and watch:

unwrap -X -fi*.txt -o. *.zip

Have a great rest of your day.