TR(1) 386BSD Reference Manual TR(1)
NAME
tr - Translate Characters.
SYNOPSIS
tr [-c] [-d | -s] string1 string2
DESCRIPTION
The tr utility copies the standard input to the standard output with
substitution or deletion of selected characters. The options specified
and the string1 and string2 operands control translations that occur
while copying characters.
The following options are available:
-c Complements the set of characters in string1 with respect to the
universe of characters whose ISO 646 [4] codes are 00 through
0377 octal.
-d Deletes all input characters in string1.
-s Squeezes all output strings of one or more instances of a single
character in string2 to a single instance of that character.
Input characters found in string1 are mapped into the
corresponding characters of string2. When string2 is shorter than
string1, string2 is extended to the length of string1 by
duplicating the last character of string2. If string2 is
explicitly a string of zero length, string2 is padded with NUL
characters.
The following operands are available:
string1
string2 Translation character strings.
If the -c option is given in conjunction with the -d option, then only
those characters found in string1 is copied to the standard output.
The following conventions can be used in string1 or string2 or both to
specify characters, character ranges, character classes, or collating
elements:
character Represents that character.
\octal A backslash followed by 1, 2, or 3 octal digits represents a
character with that encoded value. If a \octal sequence is
followed by digits, the backslash and up to three digits are
interpreted to prepare a character; subsequent digits are
interpreted as individual characters.
\character A backslash followed by any character except an octal digit
represents that character.
[c-c] Represents the range of ordered elements between the range
endpoints, inclusive.
[[:class:]] Represents all characters belonging to the defined character
class. Allowable names for class are:
alpha upper lower digit xdigit alnum
space punct print graph cntrl
The characters placed in ascending order.
[[=equiv=]] Represents all characters or collating (sorting) elements
belonging to the same equivalence class as equiv. If there
is a secondary ordering within the equivalence class, the
characters are ordered in ascending sequence. Otherwise,
they are ordered after their encoded values.
[[.cs.]] Represents a collating symbol. Multicharacter collating
symbols shall be represented as collating symbols to
distinguish them from a string of the same characters.
[x*n] Represents n repeated occurrences of the character or
collating symbol x. This expression is only valid when it
occurs in string2. If n is omitted or is zero, it is be
interpreted as large enough to extend the string2-based
sequence to the length of the string1-based sequence. If n
has a leading zero, it shall be interpreted as an octal
value. Otherwise, it shall be interpreted as a decimal
value.
Characters belonging to an equivalence class occupy the same position in
the sequence, ordered after secondary ordering.
The tr utility exits with one of the following values:
0 All input was processed successfully.
1 An error occurred.
STANDARDS
The tr utility is expected to be IEEE Std1003.2 (``POSIX'') compatible.
BSD Experimental July 30, 1991 2