Building from source basics in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to configure the source before building.

Linux CLI

./configure [1]

Drag options to blanks, or click blank then click option'

A--prefix=/usr/local

B--make

C--install

D--build

Attempts:

3 left

💡 Hint

Common Mistakes

Using --make or --install with configure causes errors because these are not configure options.

Omitting --prefix may install software in default locations, which might require root permissions.

The --prefix option sets the installation directory before building.

2fill in blank

medium

Complete the command to compile the source code using make.

Linux CLI

make [1]

Drag options to blanks, or click blank then click option'

Ainstall

B-j4

Cclean

Dconfigure

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'install' with make compiles and installs, but here we want to speed up compilation only.

Using 'configure' with make is invalid; configure is a separate script.

The -j4 option tells make to use 4 parallel jobs to speed up compilation.

3fill in blank

hard

Fix the error in the command to clean build files.

Linux CLI

make [1]

Drag options to blanks, or click blank then click option'

Adelete

Bremove

Cclear

Dclean

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'remove', 'delete', or 'clear' are not standard make targets and cause errors.

The correct make target to remove build files is 'clean'.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps words to their lengths only if length is greater than 3.

Linux CLI

{word: [1] for word in words if [2]

Drag options to blanks, or click blank then click option'

Alen(word)

Blen(word) > 3

Cword.startswith('a')

Dword.upper()

Attempts:

3 left

💡 Hint

Common Mistakes

Using word.startswith('a') filters words starting with 'a', not length.

Using word.upper() as value does not give length.

We map each word to its length using len(word), and filter words with length greater than 3.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase keys to values only if value is positive.

Linux CLI

{ [1]: [2] for k, v in data.items() if [3] }

Drag options to blanks, or click blank then click option'

Ak.upper()

Bv

Cv > 0

Dk.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using k.lower() changes keys to lowercase, not uppercase.

Filtering with v < 0 would keep negative values, not positive.

We use k.upper() as keys, v as values, and filter where v > 0 to keep positive values.

Practice

1. What is the first step you usually perform when building software from source after downloading the archive?

easy

A. Run the make command

B. Extract the archive files

C. Install the software

D. Configure the system settings

Solution

1. Step 1: Identify the initial action after download

   After downloading source code, you first need to extract the files from the archive (like .tar.gz) to access them.

2. Step 2: Understand the build sequence

   Extraction comes before configuration, compilation, and installation.

3. Final Answer:

   Extract the archive files -> Option B

4. Quick Check:

   First step = Extract [OK]

Hint: Always extract source files before anything else [OK]

Common Mistakes:

• Trying to compile before extracting files
• Running make without configuration
• Skipping extraction step

2. Which command is used to prepare the build environment by checking system settings before compiling?

easy

A. ./configure

B. gcc main.c

C. tar -xvf source.tar.gz

D. make install

Solution

1. Step 1: Identify the configuration command

   The ./configure script checks your system for required tools and sets up makefiles.

2. Step 2: Differentiate from other commands

   make install installs, tar -xvf extracts, and gcc compiles single files.

3. Final Answer:

   ./configure -> Option A

4. Quick Check:

   Prepare build = ./configure [OK]

Hint: Use ./configure to set up before compiling [OK]

Common Mistakes:

• Running make install before configure
• Confusing extraction with configuration
• Trying to compile without configuration

3. Given these commands run in order inside the source directory:

./configure
make
sudo make install

What is the expected result?

medium

A. An error occurs because sudo is used incorrectly

B. Only the software is compiled but not installed

C. The software is installed without compiling

D. The software is configured, compiled, and installed system-wide

Solution

1. Step 1: Understand each command's role

   ./configure prepares build files, make compiles the software, and sudo make install installs it with admin rights.

2. Step 2: Combine the steps' effects

   Running all three in order results in a configured, compiled, and installed program available system-wide.

3. Final Answer:

   The software is configured, compiled, and installed system-wide -> Option D

4. Quick Check:

   Configure + make + sudo install = full build [OK]

Hint: Run configure, then make, then sudo make install [OK]

Common Mistakes:

• Skipping configure step
• Not using sudo for install
• Expecting install without compilation

4. You run make install without sudo and get a permission denied error. What is the best fix?

medium

A. Run sudo make install to get admin rights

B. Run make again without install

C. Re-extract the source files

D. Skip installation and use the software from source

Solution

1. Step 1: Identify cause of permission error

   Installing usually writes to system folders needing admin rights, so permission is denied without sudo.

2. Step 2: Apply correct fix

   Using sudo make install runs install with admin privileges, fixing the error.

3. Final Answer:

   Run sudo make install to get admin rights -> Option A

4. Quick Check:

   Permission denied fix = sudo install [OK]

Hint: Use sudo for install to avoid permission errors [OK]

Common Mistakes:

• Ignoring permission errors
• Trying to reinstall without sudo
• Assuming extraction fixes install errors

5. You want to build a program from source but customize it to install in your home directory instead of system-wide. Which command should you run before make?

hard

A. sudo ./configure

B. make install PREFIX=$HOME/myprogram

C. ./configure --prefix=$HOME/myprogram

D. tar -xvf source.tar.gz --prefix=$HOME/myprogram

Solution

1. Step 1: Understand how to customize install location

   The --prefix option with ./configure sets the installation directory.

2. Step 2: Differentiate from other options

   Passing PREFIX to make install is less common; sudo is for admin rights, and tar does not set install paths.

3. Final Answer:

   ./configure --prefix=$HOME/myprogram -> Option C

4. Quick Check:

   Customize install path = configure --prefix [OK]

Hint: Use ./configure --prefix=your_path before make [OK]

Common Mistakes:

• Trying to set prefix during make install
• Using sudo unnecessarily
• Misusing tar command for install path