tr - is used to translate and/or delete characters from stdin input and writes to stdout
$ cat example.txt linux os is powerful linux os is versatile linux os is best
To change all lowercase letters in the text to uppercase and vice versa $ cat example.txt | tr [:lower:] [:upper:] or $ cat example.txt | tr [a-z] [A-Z]
To save the results written to stdout in a file $ cat example.txt | tr [a-z] [A-Z] >output.txt
To send input to tr using the input redirection and redirect the output to a file $ tr [a-z] [A-Z] < linux.txt >output.txt
To delete characters and remove spaces $ cat domain.txt www. ilugc. in www. chennaipy. org www. google. com
$ cat domains.txt | tr -d ''
To remove repeated characters in a sequence $ cat domains.txt www. ilugc........... innnn www. chennaipy. org www. google. com
$ cat domains.txt | tr -s ''
To delete all the letters and only leave the UID $ echo "My UID is $UID" | tr -cd "[:digit:]\n"
To break a single line of words (sentence) into multiple lines $ echo "My UID is $UID" $ echo "My UID is $UID" | tr " " "\n"
To translate multiple lines of words into a single sentence $ cat uid.txt My UID is 1000
$ tr "\n" " " < uid.txt
To translate single character, for instance, a space into a “ : ” $ echo "ilugc.in =>linux,devops,cloud,programming" | tr " " ":" $ echo "ilugc.in =>linux devops cloud programming" | tr " " ":"
regards, T.Dhanasekar