Building from Source¶

The term "build from source" means downloading the source code and compiling it yourself.

Software is usually packaged in an archived format. Commonly .tar.gz on Linux, or .zip on Windows.

Public-source or open-source repositories can also be cloned directly with Git without downloading an archived version.

Quickref¶

Options for extracting tarballs:

tar -xzvf name.tar.gz
tar -xjvf name.tar.bz2

xvf for both
z for .gz
j for .bz2

Tarballs/Archives¶

Typically, open-source programs are shipped in a .tar.gz format.

A .tar.gz file or .tar.bz2 file is a compressed tarball.

E.g., program.tar.gz is a tarball that was compressed with gzip.
The uncompressed extension of a tarball would be .tar.

The tarball contains the source code for an application.

Creating your Own Tarball¶

Create a tarball using the tar command with the -czf options.

tar -czf my-project.tar.gz ./my-project/

-czf
- -c: Creates a new archive.
- -z: Specify that you want to use gzip to compress it.
- -f: Specify the output file
./my-project/: The directory you want to create an archive from.

Download the Source Code¶

You found a program you want.

Find the source code for it (possibly under github's releases) and find the tarball.

Extracting an Archive¶

For .tar.gz files type:
```
tar -xzvf <filename>.tar.gz
```
For .tar.bz2 files type:
```
tar -xjvf <filename>.tar.bz2
```

Compiling the Source Code¶

First and foremost, use the documentation to determine how to build from source.
The compilation instructions are usually included somewhere within the project repository.

How you go about compiling the source code into an executable binary depends on the programming language the tool was written in.

For many C programs, which many of the GNU coreutils are written in, you'll either use gcc or cmake.

For example, if we were to compile Bash from source, we'd use make.

First we'd clone the repository (or download it in .tar.gz format).

git clone git://git.git.savannah.gnu.org/bash.git

This gives us the entire git repo for Bash.

According to the README file within the repository, we must run the ./configure program, then run make to compile bash.

There is also an INSTALL file containing installation instructions for further instructions, which says to run make install after compiling with make to install Bash and Bashbug.

./configure
make
make install

Then we've successfully built and installed Bash from its source code.