In a Linux environment, if you encounter difficulties, you can use the help command to get help.
Common commands are helpful: man command, help, info command
1, help command
help xxx command can only be used for internal, not external commands for
external commands xxx --help for
2, man command
Get more detailed than content with help, commonly known as Linux manual. Almost every command has a man page.
When we try to man ls command you will find the top left corner of the display "LS (1)", here, "LS" represents the name of the manual, and "(1)" indicates that the manual is in the first chapter. What is this section? There are so few chapters in the manual man
Section Number Description
1 user commands
2 system commands
3 C library calls
4 and special device files File
5 configuration file format
6 Games
7 Miscellaneous
8 Management Command
9 Linux kernel API
So simple and practical method to help the man has
1 view man pages
man [section] KEYWORD
2, lists all the help
man -a KEYWORD
3, search the man pages
man -k KEYWORD (lists all matching pages
4, print man help file path
man -w [section] KEYWORD
3, info help
Information obtained more than the man, info GNU project from the Free Software Foundation, the GNU hypertext help system that can show the GNU more complete information. Info structure like a web page, each page is divided into a 'node' '.
man and info like two collections, they have a part of the intersection, but compared with the man, info tool displays more complete information on GNU tools. If the summary information is a tool of man pages included in the info are also described, then the man page have the words "for further details please refer to page info" in.