Shell Programming (1)

1

/ETC/PASSWD: User account information

/etc/shadow: Secure user account information

/etc/group: Group account information

/etc/gshadow: Security group account information

2

ID: View the user ID and group ID of the current user

Id-u: Show only User ID

Id-u Root: Displays the root user ID

Id-u QQQQ: show Muggu User ID

3

Which python: Find python files under path path

Whereis python: Finding python files from the document index database

Locate python: Finding Python files in the database

Find/usr/bin-name python:/usr/bin directly to Python files in the hard drive directory

4

Grep-n-E ' root|muggu|^user* '/etc/passwd displays records starting with Root, Muggu, and user in the directory
Grep-n-E ' [[:d igit:]] '/etc/passwd displays the digital character record in the directory
Grep-n-E ' [[: Alpha:] '/etc/passwd Displays the directory context character record
Grep-n ' [0-9]\{4,\} '/etc/group displays group information records with user group ID greater than or equal to four digits

5

Image processing tools under the Gimp:linux

6

List all files by time by default sort

List all files in chronological order from near to far

List all files in chronological order from far to near

7

View the/home directory, matching the number of D at the beginning

8

Add New User User7

View and count the number of users in the/home directory

Summarize

Through this experiment, I have a new understanding of shell programming, and understand the function and usage of various shell commands. The content of regular expressions also takes more time to learn.

Shell Programming (1)