Basic Unix commands-3

11. uname command

Syntax: uname [options]

Description:    Used to print system Information

-s    prints the kernel name
-n    print the network node hostname
-r    prints the kernel release
-v    print the kernel version
-m    prints the machine hardware name
-o    prints the operating system

12. bc command

It is used for command line calculator. It is similar to basic calculator.

Syntax: bc [option]

bc starts by processing code from all the files listed on the command line in the order listed. After processing all the files bc reads from the standard input. Code is executed as it is read.

-q    To avoid bc welcome message
-l    To include math library functionalities
quit    to quit the calculator.

13. tty Command

prints the file name of the terminal connected to standard input. It writes the name of the terminal that is connected to standard input onto standard output.
It does not require any additional argument

Syntax: tty

14. stty command

It sets certain terminal I/O modes for the device that is the current standard input. Without arguments, it writes the settings of certain modes to standard output.

Syntax: stty

15. cat Command

Main functions of cat commands are

  1. to create new files
  2. Display the contents of an existing file
  3. Concatenate the content of multiple files and display it.

syntax: cat [options] [file name]

Options

-b    add line numbers to non blank lines
-e    displays a $ (dollar character) at the end of each line
-n    add line numbers to all lines
-s    removes all the blank lines and replace it to single line.
-t    show ^I instead of tabs.

#creating new file
cat > file-name.txt

Above syntax creates test.txt file and allow us to insert content in this file.
After inserting content you can use clt+d to exit the file.
If file with same name exist then it will overwrite that file.
Combining two text files

cat test.txt file.txt

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