tr

Additional Notes

tr is a text-processing command used to translate, squeeze, or delete characters from standard input. It performs character-level transformations like uppercasing, deleting characters, or collapsing repeated characters.

tr works on characters only, not words or regular expressions. Use -d to delete and -s to squeeze repeated characters.

Syntax

tr [options] [file...]

Parameters

• options: Flags that change how tr behaves.
• file: Text file to read or process.
• set1: Characters to translate, squeeze, or delete.

Common Options

• -d SET: Delete characters in SET.
• -s SET: Squeeze repeated characters.
• -c SET: Use the complement of SET.

Examples

echo "hello" | tr a-z A-Z
echo "a  b   c" | tr -s " "
echo "phone: 123-456" | tr -d "-"

Practical Notes

tr works on characters, not words or regular expressions.