Of course! The ./configure script is a fundamental part of the build process for software from source code on Unix-like systems (Linux, macOS, etc.). It's not a command for configuring Python itself, but rather a script that comes with other software packages to prepare them for compilation.

Let's break down what ./configure does, why you use it, and how it relates to Python.

What is ./configure?

Think of building software from source like a complex recipe. Before you start cooking, you need to make sure you have all the right equipment (dependencies) and that the recipe is adapted for your specific kitchen (your system).

The ./configure script is the "preparation" step. It's a shell script (usually generated by autoconf) that does the following:

• Checks System Dependencies: It checks your system for necessary libraries, tools (like a C compiler), and other software required to build the package. For example, a web server might need OpenSSL, while a video editor might need FFmpeg.
• Determines System Details: It figures out specifics about your environment, such as where to install files, what compiler flags to use, and whether your system is 32-bit or 64-bit.
• Generates Makefiles: This is its most important job. It reads a template file (Makefile.in) and uses the information it gathered to create a final, customized Makefile. The Makefile contains the actual instructions (the "recipe steps") for the compiler (like make, make install) to follow.

In short: ./configure translates generic source code into a build system specifically tailored for your computer.

How to Use ./configure (The General Workflow)

When you download a software package (e.g., from sourceforge or GitHub) and it contains a configure script, you typically follow these steps:

# 1. Navigate to the source directory
cd /path/to/the/software-source
# 2. Run the configure script with desired options
#    The leading './' is important; it tells the shell to look for the
#    script in the current directory.
./configure --option1=value --with-some-library
# 3. Compile the source code using the generated Makefile
make
# 4. (Optional) Install the compiled software to your system
#    This often requires administrator (sudo) privileges.
sudo make install

Common ./configure Options

You can see all available options by running ./configure --help. Here are some of the most common ones:

./configure and Python: The Connection

This is where your question gets interesting. You will encounter ./configure in two main scenarios related to Python.

Scenario A: Building a Python Extension Module

This is the most common reason you'd run ./configure "with Python." Many Python packages, especially those that need high performance (like NumPy, SciPy, or database drivers), have a core written in C. To build these, you use a tool called setuptools and its command-line tool setup.py.

Under the hood, setup.py often calls ./configure if it finds a configure script in the package's source. It automatically passes the correct options to tell the C compiler where to find your Python installation.

Example: Building a hypothetical C extension

# 1. Install the necessary build tools for your OS
#    On Debian/Ubuntu:
sudo apt-get install python3-dev build-essential
#    On Fedora/CentOS:
sudo dnf install python3-devel gcc
# 2. Navigate to the extension's source directory
cd my-python-extension
# 3. Build and install the extension using pip
#    pip will run setup.py, which in turn runs ./configure
pip install .

You don't usually see or control the ./configure step in this case; pip handles it for you.

Scenario B: Building Python Itself from Source

If you want to compile Python from its source code (e.g., to get a specific version, enable/disable features, or create a custom build), you would use ./configure directly on the Python source.

The Python source code includes a sophisticated configure script with many options to customize the build.

Example: Building a custom Python 3.10 installation

# 1. Download the Python source code
wget https://www.python.org/ftp/python/3.10.0/Python-3.10.0.tgz
tar -xzf Python-3.10.0.tgz
cd Python-3.10.0
# 2. Run the configure script for Python
#    This example builds Python in a local directory to avoid overwriting the system Python.
./configure --enable-optimizations --prefix=/usr/local/python-3.10
# 3. Compile and install
make -j 8  # Use multiple cores to speed up compilation
sudo make install
# 4. Use your new Python installation
/usr/local/python-3.10/bin/python3 --version
# Python 3.10.0

You can see all the options for configuring Python itself by running ./configure --help in the source directory. Common options include --enable-optimizations, --with-pydebug, and --prefix.

Troubleshooting Common Errors

• bash: ./configure: No such file or directory

  • Cause: You are not in the correct directory that contains the configure script.
  • Solution: Use ls to list the files in the current directory and cd to navigate to the right one.

• Permission denied

  • Cause: The script does not have execute permissions.
  • Solution: Run chmod +x configure to make it executable.

• error: ... library not found or fatal error: ...h: No such file or directory

  • Cause: A required dependency (like a C library or its development headers) is missing.
  • Solution: Install the necessary development packages for your operating system (e.g., libssl-dev, python3-dev, build-essential).

• ./configure: bad variable name

  • Cause: You might have typed an option incorrectly, like using a hyphen instead of an underscore _ (e.g., --with-openssl is correct, --with-ssl is not).
  • Solution: Double-check the option name by running ./configure --help.