Linux Shell Scripting Cookbook - Third Edition

Deleting characters using tr

The tr command has an option -d to delete a set of characters that appear on stdin using the specified set of characters to be deleted, as follows:

$ cat file.txt | tr -d  '[set1]'
#Only set1 is used, not set2

Consider this example:

$ echo "Hello 123 world 456" | tr -d '0-9'
Hello world
# Removes the numbers from stdin and print