32v 1m tr
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TR(1) UNIX Programmer's Manual TR(1)
Contents
NAME
tr - translate characters
SYNOPSIS
tr [ -cds ] [ string1 [ string2 ] ]
DESCRIPTION
_T_r copies the standard input to the standard output with substitution or deletion of selected characters. Input characters found in _s_t_r_i_n_g_1 are mapped into the correspond- ing characters of _s_t_r_i_n_g_2. When _s_t_r_i_n_g_2 is short it is pad- ded to the length of _s_t_r_i_n_g_1 by duplicating its last charac- ter. Any combination of the options -cds may be used: -c complements the set of characters in _s_t_r_i_n_g_1 with respect to the universe of characters whose ASCII codes are 01 through 0377 octal; -d deletes all input characters in _s_t_r_i_n_g_1; -s squeezes all strings of repeated output characters that are in _s_t_r_i_n_g_2 to single characters.
In either string the notation _a-_b means a range of charac- ters from _a to _b in increasing ASCII order. The character `\' followed by 1, 2 or 3 octal digits stands for the char- acter whose ASCII code is given by those digits. A `\' fol- lowed 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
SEE ALSO
ed(1), ascii(7)
BUGS
Won't handle ASCII NUL in _s_t_r_i_n_g_1 or _s_t_r_i_n_g_2; always deletes NUL from input.