@(#)tr.1 6.2 (Berkeley) 09/03/88

.AT 3 tr - translate characters tr [ -cds ] [ string1 [ string2 ] ] Tr copies the standard input to the standard output with substitution or deletion of selected characters. Input characters found in string1 are mapped into the corresponding characters of string2 . When string2 is short it is padded to the length of string1 by duplicating its last character. Any combination of the options -cds may be used: -c complements the set of characters in string1 with respect to the universe of characters whose ASCII codes are 0 through 0377 octal; -d deletes all input characters in string1; -s squeezes all strings of repeated output characters that are in string2 to single characters.

In either string the notation a - b means a range of characters from a to b in increasing ASCII order. The character `\e' followed by 1, 2 or 3 octal digits stands for the character whose ASCII code is given by those digits. A `\e' followed by any other character stands for that character.

The following example creates a list of all the words in `file1', each on a separate line, in `file2', where a word is taken to be a string of alphabetics. The second string is quoted to protect `\e' from the Shell. 012 is the ASCII code for newline.

tr -cs A-Za-z \'\e012\' <file1 >file2 ed(1), expand(1), ascii(7)