LPIC-2 206.1 — Make and Install Programs from Source

Exam topic 206.1 — Make and Install Programs from Source (weight: 2). Covers the full cycle of downloading, configuring, compiling, and installing a program from source code.

Why Build from Source

Sometimes the program you need is not in the distribution’s repository. Or you want to review the code before installation, enable non-standard options, or build for a specific architecture. A package manager like apt or yum handles dependencies automatically, but with a manual build you handle everything yourself.

Warning: When installing from source, there is no dependency manager. All required libraries and compilers must be installed manually before the build begins.

Install basic development tools first:

# Red Hat / CentOS / Fedora
yum groupinstall "Development Tools"

# Debian / Ubuntu
apt-get install build-essential

Where to Store Source Code

By GNU standard, source code is stored in /usr/src. That is the conventional place for archives before extraction. You can work in any directory during the build (e.g., /tmp or your home directory), but /usr/src is the default location for source code.

/usr/src/
    curl-7.46.0/       <- extracted source tree
    curl-7.46.0.tar.gz <- original archive

Important: For the exam — /usr/src is the default source code storage location.

Extracting Archives

Source code is most often distributed as a compressed tarball. Three main compression formats: gzip (.tar.gz / .tgz), bzip2 (.tar.bz2), and xz (.tar.xz).

Extraction with GNU tar (recommended)

# gzip (.tar.gz or .tgz)
tar zxvf archive.tar.gz

# bzip2 (.tar.bz2)
tar jxvf archive.tar.bz2

# xz (.tar.xz)
tar Jxvf archive.tar.xz

Flags: z = gzip, j = bzip2, J = xz, x = extract, v = verbose, f = filename.

Two-step extraction (for old tar without compression support)

# Step 1: decompress
gunzip archive.tar.gz      # or: gzip -d archive.tar.gz
bunzip2 archive.tar.bz2    # or: bzip2 -d archive.tar.bz2
unxz archive.tar.xz        # or: xz -d archive.tar.xz

# Step 2: extract tar
tar xvf archive.tar

Creating an archive

tar czf archive.tar.gz ./mydir/

Flag c = create (as opposed to x = extract).

Tip: Save configure and make output to a log with tee:

./configure | tee ../configure.log
make | tee ../make.log

Documentation Files Before Building

Before running configure, read the files in the source directory. The program’s author may use a non-standard installation process.

Note: Not all files are present in every project. Names may also differ.

configure: What It Is and Why It Exists

configure is a shell script that checks the environment before compilation. It verifies the presence of the compiler, required libraries, and optional dependencies, then generates a Makefile.

The script is generated by GNU autoconf/automake tools. automake creates Makefile.in, and autoconf turns it into the final configure script.

./configure           # run with default settings
./configure --help    # view all available parameters

If configure cannot find a mandatory dependency, it prints an error and stops. Missing optional dependencies simply disable the corresponding feature.

What configure does

1. Checks for the compiler (usually gcc)
2. Searches for mandatory and optional libraries
3. Determines the architecture via uname (runs the config.guess script)
4. Generates Makefile from Makefile.in
5. Adapts the code to the target system

configure Parameters

./configure                      # install in /usr/local (default)
./configure --prefix=/opt        # install in /opt
./configure --prefix=/opt/sue    # install in /opt/sue

# Build for deployment to another machine (DESTDIR)
./configure --prefix=/opt/sue
make
make install DESTDIR=/tmp/sue_tmp
# All program files are now in /tmp/sue_tmp/opt/sue/

Important: --prefix sets the installation path in the final system. DESTDIR at make install time tells make where to put files right now. They are different things: DESTDIR is used for building packages or deploying to multiple machines.

Full cycle for transferring to another machine:

# On the build machine
tar zxvf sue-2.0.3.tar.gz
cd sue-2.0.3
./configure --prefix=/opt/sue
make
make install DESTDIR=/tmp/sue_tmp
cd /tmp
tar czf sue-installed.tar.gz sue_tmp/

# Copy the archive to target machines, then:
tar zxvf sue-installed.tar.gz -C /

make and Build Targets

make reads the Makefile and compiles the program. Without arguments it runs the all target (build everything).

make           # compile (target: all)
make install   # install the compiled program
make clean     # remove object files after build
make distclean # remove everything including Makefile (for full rebuild)

Tip: make install requires root — binaries are placed in system directories.

The install Utility

install copies files to the right location with correct permissions and ownership. Unlike cp, it sets permissions and owner/group in one step.

# Install binary with permissions 755 to /usr/local/bin
install -m 755 mybinary /usr/local/bin/

# Install with explicit owner and group
install -m 755 -o root -g root mybinary /usr/local/bin/

# Create a backup of the existing file before overwriting
install -b -m 755 mybinary /usr/local/bin/

# Create a directory if it does not exist
install -d /usr/local/myapp/

Note: Backup behavior with -b is controlled by the VERSION_CONTROL environment variable. Values: numbered, existing, simple, none.

uname

uname prints system information. configure uses it via the config.guess script to determine the architecture during cross-compilation.

uname
# Linux

uname -a
# Linux myhost 5.15.0-91-generic #101-Ubuntu SMP x86_64 GNU/Linux

patch

patch applies a diff file to an original file. The patch file is created by diff between the old and new versions of a file.

patch -p1 < patchfile.patch       # apply a patch
patch -R -p1 < patchfile.patch    # revert a patch
patch -s -p1 < patchfile.patch    # silent mode, errors only

The -p flag specifies how many leading path components to strip from file names in the patch. -p0 leaves the path as-is, -p1 removes the first component.

# Example: path in the patch file is /home/user/src/prog/main.c
patch -p0 < fix.patch   # looks for /home/user/src/prog/main.c
patch -p1 < fix.patch   # looks for home/user/src/prog/main.c
patch -p4 < fix.patch   # looks for main.c

If patch cannot apply part of a patch, the rejected hunks are saved to a file with the .rej extension.

Warning: patch -R assumes the old and new files are swapped. Use it to return to the original state.

Full Build Cycle

Standard process for installing a program from source:

# 1. Go to /usr/src and extract the archive
cd /usr/src
tar zxvf sue-2.0.3.tar.gz

# 2. Enter the source directory
cd sue-2.0.3

# 3. Read README and INSTALL

# 4. Run configure
./configure

# 5. Compile
make

# 6. Install (as root)
sudo make install

Installation to a non-default path:

./configure --prefix=/opt
make
sudo make install

Or using install manually:

make
sudo install -m 755 -o root -g root ./sue /usr/local/bin/sue

Exam Cheat Sheet

Paths

Commands and Utilities

Common Mistakes

• Running make install without root: permission error.
• Forgetting dependencies: configure exits with an error.
• Confusing -p0 and -p1 in patch: file not found.
• Running make before ./configure: no Makefile, command will fail.
• Installing without --prefix: program lands in /usr/local, possible conflict with package manager.

Practice Questions

Q1. Which tar flag is used to extract a .tar.bz2 archive?

Answer: -j. Full command: tar jxvf archive.tar.bz2.

Q2. Where is source code stored by default on a Linux system?

Answer: /usr/src.

Q3. What does ./configure --prefix=/opt do?

Answer: Sets /opt as the root installation path. All program files will go into /opt/bin, /opt/lib, etc.

Q4. What file does configure create, and why is it needed?

Answer: Makefile. It is read by make to compile and install the program.

Q5. What is the difference between make clean and make distclean?

Answer: make clean removes only object files (.o). make distclean removes everything generated by configure and make, including the Makefile itself, returning the source tree to its original state.

Q6. How do you apply a patch and strip the first path component from the patch file?

Answer: patch -p1 < fix.patch.

Q7. Why is the install utility better than cp for installing binaries?

Answer: install sets permissions and owner/group in one step. With -b it creates a backup of the existing file before overwriting.

Q8. Why does configure call uname?

Answer: To determine the system architecture via the config.guess script. Based on this information, configure adapts the code and compiler flags for the target platform.