How to use the command 'autoconf' (with examples)

Autoconf is a command-line tool used to generate configuration scripts that automatically configure software source code packages. This tool is widely used in the open-source community and is an essential step in the process of building and installing software.

Use case 1: Generating a configuration script

Code:

autoconf

Motivation: The autoconf command is used to generate a configuration script from either configure.ac or configure.in files. This is often the first step in configuring and compiling software from source code. By running autoconf without any arguments, the tool will search for these files and generate the configuration script configure in the current directory.

Explanation:

• autoconf: This is the command itself. When run without any arguments, it will search for the configure.ac or configure.in files and generate the configure script accordingly.

Example output:

configure.ac:12: error: possibly undefined macro: AM_INIT_AUTOMAKE

[..]

autoconf2.59x: error: something went wrong!

Use case 2: Generating a configuration script from a template

Code:

autoconf template-file

Motivation: In some cases, you may want to generate a configuration script from a specific template rather than relying on the default configure.ac or configure.in files. By providing a template file as an argument to the autoconf command, you can customize the configuration script to fit your specific requirements.

Explanation:

• autoconf: This is the command itself.
• template-file: The path to the template file that will be used to generate the configuration script.

Example output:

# Output configuration script based on the provided template file

Use case 3: Generating a configuration script and writing the output to a file

Code:

autoconf --force --output=outfile template-file

Motivation: By default, autoconf only generates the configuration script to stdout. However, sometimes you may want to save the output to a file for further usage or distribution. The --force option ensures that the configuration script is regenerated even if the input file has not changed, while the --output option specifies the filename.

Explanation:

• autoconf: This is the command itself.
• --force: Forces the regeneration of the configuration script, even if the input file has not changed.
• --output=outfile: Specifies the output filename for the generated configuration script.
• template-file: The path to the template file that will be used to generate the configuration script.

Example output:

Configuration script successfully generated and saved to outfile

Conclusion:

The autoconf command is a powerful tool for generating configuration scripts that automatically configure software source code packages. By understanding the different use cases and arguments, you can utilize this tool effectively to customize and streamline the software building process.