How to use the command help2man (with examples)
Help2man is a command-line tool utilized to generate simple man pages from an executable’s --help and --version output. A man page is a user manual for a Linux command or a specific functionality, usually written in the troff format. The help2man tool will extract the necessary information from the executable’s help and version options to create a corresponding man page.
Use case 1: Generate a man page for an executable
Code:
help2man executable
Motivation: The motivation for using this example is to generate a man page for an executable without writing the entire man page manually. By extracting information from the executable’s --help output, help2man automates the process and saves time.
Explanation: To generate a man page for an executable, simply replace “executable” with the name of the actual executable in the command. The help2man command will run the executable with the --help option to extract relevant information and format it into a man page.
Example output: The help2man command will output the generated man page for the specified executable. It will include the executable’s name, a brief description, usage instructions, and any available options or arguments.
Use case 2: Specify the “name” paragraph in the man page
Code:
help2man executable --name name
Motivation: The motivation for using this example is to customize the “name” paragraph in the generated man page. By default, help2man uses the name of the specified executable as the “name” paragraph in the man page. However, in some cases, it may be necessary to provide a different name.
Explanation: To specify the “name” paragraph in the generated man page, include the --name option followed by the desired name. Replace “executable” with the actual executable name and “name” with the desired name.
Example output: The help2man command will generate a man page for the specified executable, but with the custom “name” paragraph included. The rest of the man page content will remain the same.
Use case 3: Specify the section for the man page
Code:
help2man executable --section section
Motivation: The motivation for using this example is to specify the section under which the generated man page should be categorized. By default, help2man uses section 1 for man pages, which typically represents user commands. However, certain executables may belong to a different section, and specifying it ensures correct categorization.
Explanation: To specify the section for the generated man page, include the --section option followed by the desired section number. Replace “executable” with the actual executable name and “section” with the desired section number.
Example output: The help2man command will generate a man page for the specified executable and categorize it under the specified section. The generated man page will include the custom section number in the page header.
Use case 4: Output to a file instead of stdout
Code:
help2man executable --output path/to/file
Motivation: The motivation for using this example is to redirect the output of the help2man command to a file instead of displaying it on the terminal. This allows for easy storage, sharing, and further processing of the generated man page.
Explanation: To redirect the output of the help2man command to a file, include the --output option followed by the desired file path. Replace “executable” with the actual executable name and “path/to/file” with the desired file location.
Example output: The help2man command will generate the man page for the specified executable and save it to the specified file. The terminal will not display any output, confirming the successful redirection.
Use case 5: Display detailed help
Code:
help2man --help
Motivation: The motivation for using this example is to display detailed help information about the help2man command itself. By running help2man --help, users can access additional instructions, options, and examples to utilize the command effectively.
Explanation: Simply executing help2man --help will display detailed help information, including a description of the command, available options, and usage examples. This is useful for learning more about the command and exploring its capabilities.
Example output: The help2man command will output detailed help information about the command itself, including a summary, available options, and helpful examples. This can aid users in understanding the command’s functionality and utilizing it effectively.
Conclusion:
In conclusion, help2man is a versatile command-line tool for generating man pages from an executable’s --help and --version output. The provided use cases demonstrate how to generate a man page, customize specific sections of the man page, output to a file, and access detailed help. By leveraging the power of help2man, developers and system administrators can save time by automating the creation of man pages and improve the user experience for their software.
