Tarsnap - Compiling

System preparation

Necessary software

Before you can compile Tarsnap, you need certain programs and libraries:

A C compiler (gcc or clang), make, system header files
OpenSSL (including header files)
zlib (including header files)
Linux only: the ext2fs/ext2_fs.h header
- (which is NOT the same as the linux/ext2_fs.h header file)

On many UNIX systems all the necessary packages will already be present. We provide a few sample commands for installing the required software on systems which do not include them by default:

Debian, Ubuntu, and related Linux distributions:

sudo apt-get install gcc libc6-dev make libssl-dev zlib1g-dev e2fslibs-dev

RedHat, CentOS, SuSE, Amazon Linux, and related Linux distributions:

sudo yum install gcc make glibc-devel openssl-devel zlib-devel e2fsprogs-devel

Alpine Linux:

sudo apk add gcc libc-dev make openssl openssl-dev zlib-dev e2fsprogs-dev

macOS: in addition to the normal build toolchain (probably installed via XCode), you need the OpenSSL development library. This could be installed manually, or via a package manager:
- Homebrew:
```
brew install openssl
```
- MacPorts:
```
sudo port install openssl
```

Download verification

We recommend that everybody verify any downloaded tarballs with GnuPG.

Download the Tarsnap 2026 code signing GPG key.
Optionally, verify the key:
```
gpg --list-packets tarsnap-signing-key-2026.asc | grep signature
:signature packet: algo 1, keyid 43FE83427863740F
:signature packet: algo 1, keyid 3897F2E22E65AD3F
```
The first keyid is the Tarsnap source code signing key, while the second is Colin Percival's key (0x3897F2E22E65AD3F). These keyid values should match those on a public key server search for 0x43FE83427863740F.
If you are not familiar with GnuPG, we recommend PGP & GPG, a book by Michael W. Lucas (who also wrote Tarsnap Mastery).

Import the key. Older versions are signed with older keys.

gpg --import tarsnap-signing-key-2026.asc

Installing or upgrading Tarsnap from source

These instructions are valid for installing or upgrading; upgrading simply overwrites the previous Tarsnap files.

1. Download the source tarball and signature

If you have not done so already, download the source tarball and signed SHA256 hash file from the Tarsnap source download page.

2. Verify the files

Verify the GPG signature on the SHA256 hash file using:

gpg --decrypt tarsnap-sigs-1.0.41.asc

Verify that the SHA256 hash of the tarball matches the value in the signed SHA256 hash file.
- Linux and macOS:
```
shasum -a 256 tarsnap-autoconf-1.0.41.tgz
```
- FreeBSD:
```
sha256 tarsnap-autoconf-1.0.41.tgz
```
In either case, the displayed hash should match the one you saw in the gpg --decrypt command.

3. Compile the software

Extract the file and change into that directory.

tar -xzf tarsnap-autoconf-1.0.41.tgz

cd tarsnap-autoconf-1.0.41/

Configure Tarsnap for your system.
```
./configure
```
If the configure script complains about OpenSSL, zlib, or ext2_fs.h not being present, you didn't install the right dependent packages. Make sure that you have the "development" versions (which have the header files Tarsnap needs) and not just the "library" versions.

If you installed a library to non-standard directory (such as within your $HOME directory), please read about configure and local libraries.
Compile Tarsnap.
```
make all
```
Install (or upgrade) Tarsnap.
On most systems (Linux, macOS, etc.)
```
sudo make install
```
Other systems (without sudo)
```
su
```
```
make install
```
```
exit
```

These instructions assume that:

You have root access to your system.
You want to install Tarsnap to /usr/local/bin/.

If those assumptions are incorrect, no problem! Simply call:

./configure --prefix=/MY/OTHER/DIR

make

make install

assuming you have write access to /MY/OTHER/DIR.

After installing

If you are installing for the first time, we suggest that you proceed to Getting started with Tarsnap. If you are upgrading to a new version of Tarsnap, then no further action is required.