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TR(1)			  BSD 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 sub-
     stitution or deletion of selected characters.

     The following options are available:

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

     -c	     Same as -C	but complement the set of 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 trans-
     lated 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 conven-
		tions represents itself.

     \octal	A backslash followed by	1, 2 or	3 octal	digits represents a
		character with that encoded value.  To follow an octal se-
		quence 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 char-

     c-c	For non-octal range endpoints represents the range of charac-
		ters between the range endpoints, inclusive, in	ascending or-
		der, 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,

		See the	COMPATIBILITY section below for	an important note re-
		garding	differences in the way the current implementation in-
		terprets range expressions differently from previous implemen-

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

		alnum	     <alphanumeric characters>
		alpha	     <alphabetic characters>
		blank	     <whitespace characters>
		cntrl	     <control characters>
		digit	     <numeric characters>
		graph	     <graphic characters>
		ideogram     <ideographic characters>
		lower	     <lower-case alphabetic characters>
		phonogram    <phonographic characters>
		print	     <printable	characters>
		punct	     <punctuation characters>
		rune	     <valid characters>
		space	     <space characters>
		special	     <special 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 char-
		acters 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 in-
		cluded 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 oc-
		tal value, otherwise, it is 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 tr utility exits 0 on success,	and >0 if an error occurs.

     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

     (This should be preferred over the	traditional UNIX idiom of "tr a-z A-
     Z", since it works	correctly in all locales.)

     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"

     Previous FreeBSD implementations of tr did	not order characters in	range
     expressions according to the current locale's collation order, making it
     possible to convert unaccented Latin characters (esp. as found in English
     text) from	upper to lower case using the traditional UNIX idiom of	"tr A-
     Z a-z".  Since tr now obeys the locale's collation	order, this idiom may
     not produce correct results when there is not a 1:1 mapping between lower
     and upper case, or	when the order of characters within the	two cases dif-
     fers.  As noted in	the EXAMPLES section above, the	character class	ex-
     pressions "[:lower:]" and "[:upper:]" should be used instead of explicit
     character ranges like "a-z" and "A-Z".

     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 im-
     plementation 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 `[' char-
     acter 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 com-
     pression list which would not have	happened under a historic System V im-
     plementation.  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	er-
     rors, for example,	the -c and -s options were ignored unless two strings
     were specified.  This implementation will not permit illegal syntax.

     The tr utility conforms to	IEEE Std 1003.1-2001 ("POSIX.1").  The
     "ideogram", "phonogram", "rune", and "special" character classes are ex-

     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.

BSD			       October 13, 2006				   BSD


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