How to get help for a command in Linux?
Jul 17, 2025 am 12:55 AMThere are four ways to obtain command help in Linux: First, use --help to view basic usage, which is suitable for quickly understanding common options and parameters of commands; second, use man to view the complete man page, providing detailed command descriptions and examples; third, use info to view structured help, which is suitable for information navigation of complex commands such as gcc and make; fourth, refer to network resources and communities, such as Linux China, Stack Overflow and other platforms to obtain Chinese materials or solve specific problems. It is recommended for beginners to master it step by step from --help and man.
Getting command help in Linux is actually very simple, the key is to know several commonly used methods. In different scenarios, some commands may not have a graphical interface and are operated entirely by typing commands in the terminal. It is particularly important to quickly find help information.

Use --help
to view basic usage
Most Linux commands support the --help
parameter, which displays common usage and options for this command. For example, if you want to know how to use ls
, you can directly enter:
ls --help
You will see it lists various parameters, such as -l
is to display details, -a
is to display hidden files, etc. This method is suitable for quick viewing of basic functions and common options for commands, but the information is usually simple and does not provide much in-depth explanation.

Use man
to view the full manual page
If you need more detailed help, you can use the man
command to view the man page. for example:
man ls
This will open a paged document with a complete description of the commands, including parameters, usage examples, precautions, etc.
Operation skills:

- Press the arrow keys or spaces to turn the page
- Press
/
to search for keywords - Press
q
to exit the manual page
Some commands may not have the corresponding documents installed, and at this time, they may prompt No manual entry for xxx
, so you need to install the corresponding document package, such as man-db
or the corresponding documents of the command.
View structured help with info
(suitable for complex commands)
Some commands (such as gcc
and make
) have a lot of help information, and man
page may not be enough. You can use the info
command at this time:
info make
info
provides more structured help documents, which is a bit like early web navigation, where you can use the arrow keys and enter to jump to different chapters. Although it looks a bit old-school, the information is more systematic for complex commands.
Internet resources and communities are also good helpers
If the local help information is not clear enough, or if you prefer Chinese information, you can also search online. for example:
- Visit Linux Chinese communities (such as Linux China, SegmentFault)
- Search for
命令名linux tutorial
- Check out the discussions about Stack Overflow or Reddit
Sometimes official documentation and community experience can help you get around many pitfalls, especially when you encounter problems with specific distributions.
Basically, each of these methods has applicable scenarios. For beginners, it is recommended to start with --help
and man
. If you use it too much, you will naturally know when to use which one.
The above is the detailed content of How to get help for a command in Linux?. For more information, please follow other related articles on the PHP Chinese website!

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