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TR(1)                   FreeBSD General Commands Manual                  TR(1)

     tr - translate characters

     tr [-Ccsu] string1 string2
     tr [-Ccu] -d string1
     tr [-Ccu] -s string1
     tr [-Ccu] -ds string1 string2

     The tr utility copies the standard input to the standard output with
     substitution or deletion of selected characters.

     The following options are available:

     -C      Complement the set of characters in string1, that is ``-C ab''
             includes every character except for `a' and `b'.

     -c      Same as -C but complement the set of byte values in string1.

     -d      Delete characters in string1 from the input.

     -s      Squeeze multiple occurrences of the characters listed in the last
             operand (either string1 or string2) in the input into a single
             instance of the character.  This occurs after all deletion and
             translation is completed.

     -u      Guarantee that any output is unbuffered.

     In the first synopsis form, the characters in string1 are translated into
     the characters in string2 where the first character in string1 is
     translated into the first character in string2 and so on.  If string1 is
     longer than string2, the last character found in string2 is duplicated
     until string1 is exhausted.

     In the second synopsis form, the characters in string1 are deleted from
     the input.

     In the third synopsis form, the characters in string1 are compressed as
     described for the -s option.

     In the fourth synopsis form, the characters in string1 are deleted from
     the input, and the characters in string2 are compressed as described for
     the -s option.

     The following conventions can be used in string1 and string2 to specify
     sets of characters:

     character  Any character not described by one of the following
                conventions represents itself.

     \octal     A backslash followed by 1, 2 or 3 octal digits represents a
                character with that encoded value.  To follow an octal
                sequence with a digit as a character, left zero-pad the octal
                sequence to the full 3 octal digits.

                A backslash followed by certain special characters maps to
                special values.

                \a    <alert character>

                \b    <backspace>

                \f    <form-feed>

                \n    <newline>
                \r    <carriage return>

                \t    <tab>
                \v    <vertical tab>

                A backslash followed by any other character maps to that

     c-c        For non-octal range endpoints represents the range of
                characters between the range endpoints, inclusive, in
                ascending order, as defined by the collation sequence.  If
                either or both of the range endpoints are octal sequences, it
                represents the range of specific coded values between the
                range endpoints, inclusive.

     [:class:]  Represents all characters belonging to the defined character
                class.  Class names are:

                alnum     <alphanumeric characters>

                alpha     <alphabetic characters>

                cntrl     <control characters>

                digit     <numeric characters>

                graph     <graphic characters>

                lower     <lower-case alphabetic characters>

                print     <printable characters>

                punct     <punctuation characters>

                space     <space characters>

                upper     <upper-case characters>

                xdigit    <hexadecimal characters>

                When ``[:lower:]'' appears in string1 and ``[:upper:]''
                appears in the same relative position in string2, it
                represents the characters pairs from the toupper mapping in
                the LC_CTYPE category of the current locale.  When
                ``[:upper:]'' appears in string1 and ``[:lower:]'' appears in
                the same relative position in string2, it represents the
                characters pairs from the tolower mapping in the LC_CTYPE
                category of the current locale.

                With the exception of case conversion, characters in the
                classes are in unspecified order.

                For specific information as to which ASCII characters are
                included in these classes, see ctype(3) and related manual

     [=equiv=]  Represents all characters belonging to the same equivalence
                class as equiv, ordered by their encoded values.

     [#*n]      Represents n repeated occurrences of the character represented
                by #.  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 string2 sequence to the length of
                string1.  If n has a leading zero, it is interpreted as an
                octal value, otherwise, it's interpreted as a decimal value.

     The LANG, LC_ALL, LC_CTYPE and LC_COLLATE environment variables affect
     the execution of tr as described in environ(7).

     The following examples are shown as given to the shell:

     Create a list of the words in file1, one per line, where a word is taken
     to be a maximal string of letters.

           tr -cs "[:alpha:]" "\n" < file1

     Translate the contents of file1 to upper-case.

           tr "[:lower:]" "[:upper:]" < file1

     Strip out non-printable characters from file1.

           tr -cd "[:print:]" < file1

     Remove diacritical marks from all accented variants of the letter `e':

           tr "[=e=]" "e"

     The tr utility exits 0 on success, and >0 if an error occurs.

     System V has historically implemented character ranges using the syntax
     ``[c-c]'' instead of the ``c-c'' used by historic BSD implementations and
     standardized by POSIX.  System V shell scripts should work under this
     implementation as long as the range is intended to map in another range,
     i.e. the command ``tr [a-z] [A-Z]'' will work as it will map the ``[''
     character in string1 to the ``['' character in string2.  However, if the
     shell script is deleting or squeezing characters as in the command ``tr
     -d [a-z]'', the characters ``['' and ``]'' will be included in the
     deletion or compression list which would not have happened under a
     historic System V implementation.  Additionally, any scripts that
     depended on the sequence ``a-z'' to represent the three characters ``a'',
     ``-'' and ``z'' will have to be rewritten as ``a\-z''.

     The tr utility has historically not permitted the manipulation of NUL
     bytes in its input and, additionally, stripped NUL's from its input
     stream.  This implementation has removed this behavior as a bug.

     The tr utility has historically been extremely forgiving of syntax
     errors, for example, the -c and -s options were ignored unless two
     strings were specified.  This implementation will not permit illegal

     The tr utility conforms to IEEE Std 1003.1-2001 (``POSIX.1'').

     It should be noted that the feature wherein the last character of string2
     is duplicated if string2 has less characters than string1 is permitted by
     POSIX but is not required.  Shell scripts attempting to be portable to
     other POSIX systems should use the ``[#*]'' convention instead of relying
     on this behavior.  The -u option is an extension to the IEEE Std
     1003.1-2001 (``POSIX.1'') standard.

FreeBSD 11.0-PRERELEASE        October 11, 1997        FreeBSD 11.0-PRERELEASE


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