View help related commands in Linux

Time:2021-10-14

-H or — help help help command

To view the help of shell built-in commands, you can use – H or — help

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The code is as follows:

#wget –help

Or it can be used with the less command for easy viewing

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The code is as follows:

#wget –help | less

Or I can directly check the usage and explanation of the parameters I want to use:

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The code is as follows:

#wget –help | grep proxy</p>
<p>#help cd

Info command usage details

Some commands may not have a man manual or are not in the specified place. At this time, the command may have an info document.

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The code is as follows:

#info tar

Detailed explanation of apropos command

Equivalent to man   – k   Command, fuzzy search related commands with keywords. For example, I want to search network related commands:

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The code is as follows:

#apropos network

Of course, the database used for search needs to be established first. When an error occurs in the user command, the whatis database is not established. Input:

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The code is as follows:

#makewhatis

Establish a database for search

Get a short description of the index

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The code is as follows:

#whatis ls

Of course, the database used for search needs to be established first. When an error occurs in the user command, the whatis database is not established. Input:

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The code is as follows:

#makewhatis

Establish a database for search

Linux system provides relatively rich help manuals (man). Man is the abbreviation of manual, which is often used in daily Linux system management. Let’s talk about man today. Man also provides its own help manual, which can be viewed through man.

 
The man page is roughly divided into the following parts:

Name: simple command, data name and description

Synopsis: a brief introduction to command syntax

Description: a relatively complete description, which needs to be read carefully

Option: description of all available options listed in synopsis

Commands: commands can be used in this software when the software is executing

Files: the files to which this software or data is used or referenced or linked

See alse: refer to other instructions related to this command

Example: some examples you can refer to. This is best used

Bugs: are there any related bugs

Manual for exporting LS command:

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The code is as follows:

man ls | col -bfp > ls.txt

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