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echo(1)                          User Commands                         echo(1)



NAME
       echo - echo arguments

SYNOPSIS
       /usr/bin/echo [string...]

DESCRIPTION
       The  echo  utility writes its arguments, separated by BLANKs and termi-
       nated by a NEWLINE, to the standard output. If there are no  arguments,
       only the NEWLINE character will be written.

       echo  is useful for producing diagnostics in command files, for sending
       known data into a pipe, and for displaying the contents of  environment
       variables.

       The  C shell, the Korn shell, and the Bourne shell all have echo built-
       in commands, which, by default, will be invoked if the user calls  echo
       without  a full pathname. See shell_builtins(1). sh's echo, ksh's echo,
       and /usr/bin/echo understand the back-slashed escape characters, except
       that  sh's echo does not understand \a as the alert character. In addi-
       tion,  ksh's  echo,  does  not  have  an  -n  option.  sh's   echo  and
       /usr/bin/echo  only have an -n option if the SYSV3 environment variable
       is set (see ENVIRONMENT VARIABLES below). If it is, none of  the  back-
       slashed  characters  mentioned  above  are  available.  csh's  echo and
       /usr/ucb/echo, on the other hand, have an -n option, but do not  under-
       stand the back-slashed escape characters.

OPERANDS
       The following operand is supported:

       string   A  string  to be written to standard output. If any operand is
                "-n", it will be treated as a string, not an option. The  fol-
                lowing  character  sequences  will be recognized within any of
                the arguments:

                \a       Alert character.




                \b       Backspace.



                \c       Print line without new-line. All characters following
                         the \c in the argument are ignored.



                \f       Form-feed.



                \n       New-line.



                \r       Carriage return.



                \t       Tab.



                \v       Vertical tab.



                \\       Backslash.



                \0n      Where  n  is  the 8-bit character whose ASCII code is
                         the 1-, 2- or 3-digit octal number representing  that
                         character.




USAGE
       Portable  applications  should  not  use  -n (as the first argument) or
       escape sequences.

       The printf(1) utility can be used portably to emulate any of the tradi-
       tional behaviors of the echo utility as follows:

         o  The  Solaris  2.6  operating  environment  or compatible version's
            /usr/bin/echo is equivalent to:


            printf "%b\n" "$*"

         o  The /usr/ucb/echo is equivalent to:


            if [ "X$1" = "X-n" ]

            then

                    shift

                    printf "%s" "$*"

            else

                    printf "%s\n" "$*"

            fi


       New applications are encouraged to use printf instead of echo.

EXAMPLES
       Example 1: Finding how far below root your current directory is located

       You can use echo to determine how many subdirectories  below  the  root
       directory (/) is your current directory, as follows:

         o  Echo your current-working-directory's full pathname.

         o  Pipe the output through tr to translate the path's embedded slash-
            characters into space-characters.

         o  Pipe that output through wc -w for a count of the  names  in  your
            path.


            example% /usr/bin/echo $PWD | tr '/' ' ' | wc -w


       See tr(1) and wc(1) for their functionality.

       Below are the different flavors for echoing a string without a NEWLINE:

       Example 2: /usr/bin/echo

       example% /usr/bin/echo "$USER's current directory is $PWD\c"

       Example 3: sh/ksh shells

       example$ echo "$USER's current directory is $PWD\c"

       Example 4: csh shell

       example% echo -n "$USER's current directory is $PWD"

       Example 5: /usr/ucb/echo

       example% /usr/ucb/echo -n "$USER's current directory is $PWD"

ENVIRONMENT VARIABLES
       See  environ(5) for descriptions of the following environment variables
       that affect the execution of echo: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.

       SYSV3    This  environment  variable  is  used to provide compatibility
                with  INTERACTIVE  UNIX  System  and  SCO  UNIX   installation
                scripts.  It is intended for compatibility only and should not
                be used in new scripts.



EXIT STATUS
       The following error values are returned:

       0        Successful completion.



       >>0       An error occurred.



ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).    ATTRIBUTE   TYPEATTRIBUTE  VALUE  AvailabilitySUNWcsu
       CSIenabled Interface StabilityStandard


SEE ALSO
       echo(1B),  printf(1),  shell_builtins(1),   tr(1),   wc(1),   ascii(5),
       attributes(5), environ(5), standards(5)

NOTES
       When  representing  an  8-bit  character by using the escape convention
       \0n, the n must always be preceded by the digit zero (0).

       For example, typing: echo 'WARNING:\07' will print the phrase  WARNING:
       and  sound  the  "bell" on your terminal. The use of single (or double)
       quotes (or two backslashes) is required to protect the  "\"  that  pre-
       cedes the "07".

       Following the \0, up to three digits are used in constructing the octal
       output character. If, following the \0n, you want  to  echo  additional
       digits  that are not part of the octal representation, you must use the
       full 3-digit n. For example, if you want to echo "ESC 7" you  must  use
       the  three  digits "033" rather than just the two digits "33" after the
       \0.



              tab(); lw(1.375000i) lw(1.375000i) lw(1.375000i)  lw(1.375000i).
              2   digitsIncorrect:echo"0337   |   od   -xc  produces:df0a(hex)
              337(ascii) 3 digitsCorrect:echo "00337" | od  -xc  produces:lb37
              0a00(hex) 033 7(ascii)



       For the octal equivalents of each character, see ascii(5).



SunOS 5.10                        20 Jan 2000                          echo(1)