tr – translate characters|
tr [ –cds ] [ string1 [ string2 ] ]|
Tr copies the standard input to the standard output with substitution
or deletion of selected characters (runes). 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 Complement string1: replace it with a lexicographically ordered list of all other characters.
–d Delete from input all characters in string1.
–s Squeeze repeated output characters that occur in string2 to single characters.
In either string a noninitial sequence –x, where x is any character
(possibly quoted), stands for a range of characters: a possibly
empty sequence of codes running from the successor of the previous
code up through the code for x. The character \ followed by 1,
2 or 3 octal digits stands for the character whose 16–bit
value is given by those digits. The character sequence \x followed
by 1 to 6 hexadecimal digits stands for the character whose 21–bit
value is given by those digits. A \ followed by any other character
stands for that character.
Replace all upper–case ASCII letters by lower–case.|