How to use the command `rev` (with examples)
The rev command is used to reverse a line of text or an entire file. By default, it reverses characters on a per-line basis.
Use case 1: Reverse the text string “hello”
Code:
echo "hello" | rev
Motivation: The motivation for using this example is to demonstrate how to reverse a simple text string using the rev command. This example can be useful when you want to reverse the order of characters in a string.
Explanation: The echo "hello" command outputs the string “hello” to the standard output (stdout). The | symbol is a pipe, which redirects the output of the echo command as input to the rev command. Finally, the rev command reverses the characters in the string “hello” and prints the result to the terminal.
Example output:
olleh
Use case 2: Reverse an entire file and print to stdout
Code:
rev path/to/file
Motivation: The motivation for using this example is to demonstrate how to reverse the contents of an entire file using the rev command. This can be useful when you want to view the contents of a file in reverse order.
Explanation: The rev command takes a file path as an argument and reverses the contents of that file. The reversed output is then printed to the terminal. The path/to/file argument should be replaced with the actual path to the file you want to reverse.
Example output:
.elif ecnetnes a rof noitcif yob-txet A
.nekorb yb desaeler eb nac txet eht noitcif erewhsaer dna ecnetnes eht sesrever nekorb a rof elgnis eht tahw ecnetnes eht ni htam rof elgnis eht srevid ruoF
Conclusion:
The rev command is a useful tool for reversing text. Whether you want to reverse a simple string or the contents of an entire file, the rev command can help you achieve this. By using different variations of the rev command, you can easily reverse the order of characters in a text string or view the contents of a file in reverse order.
