


In Linux, you can use the cat command to check which groups there are. This command is used to connect files and print to the standard output device. The syntax is "cat /etc/group"; "/ect/group" file It is the user group configuration file, that is, all the information of the user group is stored in this file.
#The operating environment of this tutorial: linux7.3 system, Dell G3 computer.
How to check which groups are there in Linux
The cat (full English spelling: concatenate) command is used to connect files and print to the standard output device .
The syntax is:
cat [-AbeEnstTuv] [--help] [--version] fileName
/ect/group file is the user group configuration file, that is, all the information of the user group is stored in this file.
Parameter description:
-n or --number: Number all output lines starting from 1.
-b or --number-nonblank: Similar to -n, except that blank lines are not numbered.
-s or --squeeze-blank: When encountering more than two consecutive blank lines, replace them with one blank line.
-v or --show-nonprinting: Use the ^ and M- symbols except LFD and TAB.
-E or --show-ends : Display $ at the end of each line.
-T or --show-tabs: Display TAB characters as ^I.
-A, --show-all: Equivalent to -vET.
-e: Equivalent to the "-vE" option;
-t: Equivalent to the "-vT" option;
The example is as follows:
Output result:
Related Recommended: "Linux Video Tutorial"
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