tr − tr
tr [OPTION]... SET1 [SET2]
Translate or delete characters
[sets]...
−c, −−complement
use the complement of SET1 [aliases: −C]
−d, −−delete
delete characters in SET1, do not translate
−s, −−squeeze−repeats
replace each sequence of a repeated character that is listed in the last specified SET, with a single occurrence of that character
−t, −−truncate−set1
first truncate SET1 to length of SET2
−h, −−help
Print help
−V, −−version
Print version
Translate, squeeze, and/or delete characters from standard input, writing to standard output.