tr(1)tr(1)Nametr - translate characters
Syntaxtr [-cds] [string1[string2]]
Description
The command copies the standard input to the standard output with sub‐
stitution 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 dupli‐
cating 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 backslash character (\) followed by
1, 2 or 3 octal digits stands for the character whose ASCII code is
given by those digits. A \ followed by any other character stands for
that character.
The following example creates a list of all the words in `file1' one
per line in `file2', where a word is taken to be a maximal string of
alphabetics. The second string is quoted to protect \ from the Shell.
012 is the ASCII code for newline.
tr-cs A-Za-z ´\012´ <file1 >file2
Options-c Translates complements: string1 to those not in string1.
-d Deletes all characters in string1 from output.
-s Squeezes succession of a character in string1 to one in output.
Restrictions
`\0', `\00', and `\000' are equivalent for NUL character.
`\012' is treated as octal 12 and not a NUL followed by characters 1
and 2.
See Alsoed(1), ascii(7), expand(1)tr(1)