1.\" $NetBSD: echo.1,v 1.12 2002/02/08 01:22:00 ross Exp $ 2.\" 3.\" Copyright (c) 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Kenneth Almquist. 8.\" Copyright 1989 by Kenneth Almquist 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. All advertising materials mentioning features or use of this software 19.\" must display the following acknowledgement: 20.\" This product includes software developed by the University of 21.\" California, Berkeley and its contributors. 22.\" 4. Neither the name of the University nor the names of its contributors 23.\" may be used to endorse or promote products derived from this software 24.\" without specific prior written permission. 25.\" 26.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36.\" SUCH DAMAGE. 37.\" 38.\" @(#)echo.1 8.1 (Berkeley) 5/31/93 39.\" 40.Dd May 31, 1993 41.Dt ECHO 1 42.Os 43.Sh NAME 44.Nm echo 45.Nd produce message in a shell script 46.Sh SYNOPSIS 47.Nm 48.Op Fl n | Fl e 49.Ar args ... 50.Sh DESCRIPTION 51.Nm 52prints its arguments on the standard output, separated by spaces. 53Unless the 54.Fl n 55option is present, a newline is output following the arguments. 56The 57.Fl e 58option causes 59.Nm 60to treat the escape sequences specially, as described in the following 61paragraph. 62The 63.Fl e 64option is the default, and is provided solely for compatibility with 65other systems. 66Only one of the options 67.Fl n 68and 69.Fl e 70may be given. 71.Pp 72If any of the following sequences of characters is encountered during 73output, the sequence is not output. Instead, the specified action is 74performed: 75.Bl -tag -width indent 76.It Li \eb 77A backspace character is output. 78.It Li \ec 79Subsequent output is suppressed. This is normally used at the end of the 80last argument to suppress the trailing newline that 81.Nm 82would otherwise output. 83.It Li \ef 84Output a form feed. 85.It Li \en 86Output a newline character. 87.It Li \er 88Output a carriage return. 89.It Li \et 90Output a (horizontal) tab character. 91.It Li \ev 92Output a vertical tab. 93.It Li \e0 Ns Ar digits 94Output the character whose value is given by zero to three digits. 95If there are zero digits, a nul character is output. 96.It Li \e\e 97Output a backslash. 98.El 99.Sh HINTS 100Remember that backslash is special to the shell and needs to be escaped. 101To output a message to standard error, say 102.Pp 103.D1 echo message \*[Gt]\*[Am]2 104.Sh BUGS 105The octal character escape mechanism 106.Pq Li \e0 Ns Ar digits 107differs from the 108C language mechanism. 109.Pp 110There is no way to force 111.Nm 112to treat its arguments literally, rather than interpreting them as 113options and escape sequences. 114