ERC - Etersoft Archive Tool

Universal command-line archive manager with a single interface for all archive formats.

Description

ERC provides a unified interface to work with various archive formats. It uses patool as the primary backend, with 7z as a fallback when patool is not available.

Installation

ALT Linux

apt-get install erc

Dependencies

• patool (recommended) - provides support for many formats
• p7zip or 7-zip - fallback backend, also used for 7z format

Usage

Commands

Command	Description
a, create, pack, add	Create archive or add files
x, extract, unpack	Extract files from archive
l, list	List archive contents
t, test, check	Test archive integrity
type	Print archive type
basename	Print predicted directory name for archive
repack, conv	Convert archive to another format
formats	List supported formats
b, bench, benchmark	Run CPU benchmark
diff	Compare two archives
search, grep	Search in archive files

Commands can also be used with a dash prefix: -a, -x, -l, -t, -b.

Options

Option	Description
-h, --help	Show help
-V, --version	Show version
-q, --quiet	Quiet mode
-f, --force	Overwrite existing files
-C DIR, --directory DIR	Extract to specified directory
--here, --no-subdir	Extract as-is without creating a subdirectory
--flat, -j, --junk-paths	Extract all files stripping directory structure
--use-patool	Force patool backend
--use-7z	Force 7z backend

Also supported as aliases for -C: --extract-to, --destination, --outdir. Long options accept = syntax.

Extraction Behavior

When extracting an archive, erc decides where to place the files:

• Single file in archive — extracted directly to the current directory
• Single directory in archive — renamed to match the archive basename (e.g. data.zip containing src/ extracts as data/)
• Multiple files or directories — extracted into a subdirectory named after the archive (e.g. test.zip → test/)

Use erc basename archive.tar.gz to see the predicted directory name.

Modifiers:

• --here / --no-subdir — extract as-is without creating a subdirectory
• --flat / -j — extract all files stripping directory structure
• -C DIR — extract into the specified directory

Examples

Create archive:

erc a archive.zip file1.txt file2.txt   # create zip with files
erc dir                                  # pack directory to dir.zip
erc file.txt zip:                        # pack to zip using format specifier
erc a archive.tar.gz directory/         # create tar.gz archive

Extract archive:

erc archive.zip                          # extract (implicit command)
erc x archive.tar.gz                     # extract with explicit command
erc -C dir archive.zip                   # extract directly into dir
erc --directory=dir archive.tar.gz       # same with long option
erc --here archive.zip                   # extract without creating subdirectory
erc --flat archive.zip                   # extract all files stripping paths
erc --flat -C dir archive.zip            # strip paths into target directory
unerc archive.7z                         # extract using unerc alias
erc basename archive.tar.gz              # print predicted directory name

List and test:

erc l archive.zip                        # list contents
erc t archive.7z                         # test integrity
erc type archive.tar.xz                  # print archive type

Convert formats:

erc repack archive.zip archive.7z        # repack zip to 7z
erc archive.zip 7z:                      # repack using format specifier
erc -f repack old.tar.gz new.tar.xz      # force overwrite target

Utilities

erc

Main archive tool with all commands.

unerc

Symlink to erc that defaults to extract mode.

ercat

Output contents of compressed files to stdout (like bzcat, zcat).

ercat /var/log/messages.1.gz | grep error
ercat file.bz2 file.xz                   # concatenate multiple files
ercat --quiet file.gz                    # suppress extra output

Supported formats: gz, bz2, xz, lzma, zst, lz4, Z

Backends

ERC supports two backends:

1. patool (default if installed) - supports many archive formats
2. 7z (fallback) - uses 7-zip tools (7z, 7za, 7zr, 7zz)

Backend selection

erc --use-patool a archive.zip files     # force patool
erc --use-7z x archive.7z                # force 7z
ERC_BACKEND=patool erc a test.zip dir    # via environment variable
ERC_BACKEND=7z erc x test.7z             # via environment variable

Supported Formats

With patool backend

All formats supported by patool: zip, 7z, tar, rar, cab, arj, cpio, rpm, deb, iso, and many more.

With 7z backend

zip, 7z, tar, tar.gz, tar.bz2, tar.xz, tar.zst, and other 7-zip supported formats.

Special formats

• exe, dll - extract resources using 7z
• AppImage - extract using built-in --appimage-extract
• squashfs - extract using 7z
• flatpak - extract, list and test bundles via ostree (requires ostree)

Run erc formats for a complete list of supported formats.

Running Tests

cd tests
bats *.bats                              # run all tests
bats erc.bats                            # run specific test file

License

GNU Affero General Public License v3.0 (AGPLv3)

Links

• GitHub: https://github.com/Etersoft/erc
• Wiki: http://wiki.etersoft.ru/ERC
• EEPM: http://wiki.etersoft.ru/EEPM
• patool: https://github.com/wummel/patool
• Issues: https://github.com/Etersoft/erc/issues