Linux commands lsattr, chattr, man

1, man command, you can view the manual

Configuration Location/etc/man.conf

Manpath Decision Manual Query location

Mansect determining the Order of man queries

Man's query

Common uses of Linux man:
man section cmd: direct Specify a specific chapter within the Search man page, such as Span style= "Color:blue" >man 5 passwd directly into file format version of Help
man-a cmd : Open help with the same name in all sections, for example Man–a passwd, you first enter a passwd (1) command version passwd Help, and you press the Q key to enter passwd (5), passwd configuration file Format help
man-aw cmd: Show path of all manuals files for all cmd, such as Man-aw passwd is
/usr/share/man/man1/passwd.1.gz
/usr/share/man/man5/passwd.5.gz
Specifies the search path of the manual file, such as Man-m/home/mysql/man MySQL display is the help of your installed MySQL, not the system comes with the old version of MySQL Help
man cmd| col-b > Cmd.txt: Output man manual information to a text file

man Brief introduction:
The man in Linux is very powerful, and the manual is divided into sections, which can be used to specify a different section to navigate by using the man, each of which has the following meanings:

• 1–user Commands General user commands
• 2-system Calls System invoke commands, such as open,write (through this, at least it is convenient to find the call this function, which need to add a header file)
• 3-c Library Functions C function Gallery commands, such as Printf,fread
• 4-devices and special files is a special file, which is the various device files under/dev man HD
• 5-file formats and conventions refers to the format of a file, such as the Man 5 passwd, which shows the meaning of each field in this file/etc/passwd
• 6-games for Linux is reserved for games and is defined by each game itself
• 7-miscellanea Miscellaneous, such as macro command packages, conventions, and so on.
• 8-system Administration Tools and Deamons are commands for system administration that can only be used by root, such as Ifconfig
• 9-Other (Linux-specific) for storing the kernel The documentation for the routine program.
• N New documents that may be moved to a more appropriate area.
• o old documents may be retained for a period of time. The
• l local document, which is related to this particular system.

Man command format:
Man [option] name:name is usually the name of the Help document, corresponding to the command name, function name, or configuration file name (with suffix!). ), such as
Man nsswitch.conf: View the Help documentation for the/etc/nsswitch.conf file
Man networks: View the Help documentation for the/etc/sysconfig/networks file

To view the Help documentation for a specific language version: set the environment variable LANG=ZH_CN before executing the man query

Man's configuration file/etc/man.config:
If you don't want to specify the path with-M every time man cmd, you can modify the configuration file to add content such as
Manpath/home/mysql/man

Man 's search order in each section can be modified in the following way, but it is generally not recommended.
Mansect 1:8:2:3:4:5:6:7:9:tcl:n:l:p:o

2, Lsattr

Show hidden properties of a file

Chattr to modify hidden properties of a file

CHATRR +a Tmp.txt so that files can only be added, cannot be modified, can not be deleted, suitable for various log files

Chattr +i tmp.txt to make the file unable to be deleted


a：即append，设定该参数后，只能向文件中添加数据，而不能删除，多用于服务器日志文件安全，只有root才能设定这个属性。
i：设定文件不能被删除、改名、设定链接关系，同时不能写入或新增内容。i参数对于文件 系统的安全设置有很大帮助。

Reference:

1, http://www.runoob.com/linux/linux-comm-lsattr.html

Linux commands lsattr, chattr, man