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TR(1)			  BSD General Commands Manual			 TR(1)

NAME
     tr	-- translate characters

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

DESCRIPTION
     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 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 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.

     \character
		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-
		acter.

     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,
		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:]''	ap-
		pears 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 posi-
		tion in	string2, it represents the characters pairs from the
		tolower	mapping	in the LC_CTYPE	category of the	current	lo-
		cale.

		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
		pages.

     [=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's interpreted as a decimal value.

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

EXAMPLES
     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"

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

COMPATIBILITY
     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 ``[''
     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	dele-
     tion 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	er-
     rors, for example,	the -c and -s options were ignored unless two strings
     were specified.  This implementation will not permit illegal syntax.

STANDARDS
     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.

BSD			       October 11, 1997				   BSD

NAME | SYNOPSIS | DESCRIPTION | ENVIRONMENT | EXAMPLES | DIAGNOSTICS | COMPATIBILITY | STANDARDS

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