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echo(1)								      echo(1)



NAME

  echo - Writes	its arguments to standard output

SYNOPSIS

  echo [-n] [string...]

  [Tru64 UNIX]	The -n option is valid only if the environment variable
  CMD_ENV is set to bsd.

				     Note

       The C shell has a built-in version of the echo command.	If you are
       using the C shell, and want to guarantee	that you are using the com-
       mand described here, you	must specify the full path /usr/bin/echo.
       See the csh(1) reference	page for a description of the built-in com-
       mand.

STANDARDS

  Interfaces documented	on this	reference page conform to industry standards
  as follows:

  echo:	 XCU5.0

  Refer	to the standards(5) reference page for more information	about indus-
  try standards	and associated tags.

OPTIONS

  -n  [Tru64 UNIX]  No newline is added	to the output. The -n option is	valid
      only if the environment variable CMD_ENV is set to bsd. Otherwise	any
      -n operand is treated as a string	rather than as a option. See the
      printf(1)	reference page for use in portable applications.

OPERANDS

  string
      The string to be displayed on standard output. The echo command recog-
      nizes the	following special characters in	the string:

      \a  Displays an alert character.

      \b  Displays a backspace character.

      \c  Suppresses the newline character. All	characters following \c	in
	  the arguments	are ignored.

      \f  Displays a formfeed character.

      \n  Displays a newline character.

      \r  Displays a carriage-return character.

      \t  Displays a tab character.

      \v  Displays a vertical tab character.

      \\  Displays a backslash character.

      \number
	  Displays an 8-bit character whose value is the 1-, 2-	or 3-digit
	  octal	number,	number.	 The first digit of number must	be a 0
	  (zero).

DESCRIPTION

  The echo command writes the specified	string to standard output, followed
  by a newline character.

  The arguments	are separated by spaces. Use the echo command to produce
  diagnostic messages in command files and to send data	into a pipe.  If
  there	are no arguments, the echo command outputs a newline character.

  [Tru64 UNIX]	The echo command described here	is the program /usr/bin/echo.
  Both csh and sh shells contain built-in echo subcommands, which do not
  necessarily work in the same way as the /usr/bin/echo	command.

EXIT STATUS

  The following	exit values are	returned:

  0   Successful completion.

  >>0  An error occurred.

EXAMPLES

   1.  To write	a message to standard output, enter:
	    echo Please	insert diskette	. . .

   2.  To display a message containing special characters as listed in
       DESCRIPTION, enclose the	message	in quotes, as follows:
	    echo "\n\n\nI'm at lunch.\nI'll be back at 1 p.m."

       This skips three	lines and displays the message:
	    I'm	at lunch.
	    I'll be back at 1 p.m.


					Note

	 You must enclose the message in quotation marks if it contains
	 escape	sequences such as \n.  Otherwise, the shell treats the
	 backslash (\) as an escape character.	The previous command example,
	 entered without the quotes, results in	the following output:
	      nnnI'm at	lunch.nI'll be back at 1 p.m.



   3.  To use echo with	pattern-matching characters, enter:
	    echo The back-up files are:	*.bak

       This displays the message The back-up files are:	and then displays the
       file names in the current directory ending with .bak.

   4.  To add a	single line of text to a file, enter:
	    echo Remember to set the shell search path to $PATH. >>>>notes

       This adds the message to	the end	of the file notes after	the shell
       substitutes the value of	the PATH shell variable.

   5.  To write	a message to the standard error	output (sh only), enter:
	    echo Error:	file already exists. >>&&2

       Use this	in shell procedures to write error messages.  If the >>&&2 is
       omitted,	then the message is written to the standard output.

ENVIRONMENT VARIABLES

  The following	environment variables affect the execution of echo:

  CMD_ENV
      [Tru64 UNIX]  This variable must set to bsd for the -n option to be
      valid.  Otherwise	any -n operand is treated as a string member.

  LANG
      Provides a default value for the internationalization variables that
      are unset	or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables	contain	an invalid setting, the	utility	behaves	as if none of
      the variables had	been defined.

  LC_ALL
      If set to	a non-empty string value, overrides the	values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for	the interpretation of sequences	of bytes of
      text data	as characters (for example, single-byte	as opposed to multi-
      byte characters in arguments).

  LC_MESSAGES
      Determines the locale for	the format and contents	of diagnostic mes-
      sages written to standard	error.

  NLSPATH
      Determines the location of message catalogues for	the processing of
      LC_MESSAGES.

SEE ALSO

  Commands:  csh(1), ksh(1), printf(1),	Bourne shell sh(1b), POSIX shell
  sh(1p)

  Environment:	environ(5)

  Standards:  standards(5)