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.\"-
.\" Copyright (c) 1990, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the Institute of Electrical and Electronics Engineers, Inc.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd October 5, 2016
.Dt ECHO 1
.Os
.Sh NAME
.Nm echo
.Nd write arguments to the standard output
.Sh SYNOPSIS
.Nm
.Op Fl n
.Op Ar string ...
.Sh DESCRIPTION
The
.Nm
utility writes any specified operands, separated by single blank
.Pq Ql "\ "
characters and followed by a newline
.Pq Ql \en
character, to the standard
output.
.Pp
The following option is available:
.Bl -tag -width flag
.It Fl n
Do not print the trailing newline character.
.El
.Pp
The end-of-options marker
.Fl Fl
is not recognized and written literally.
.Pp
The newline may also be suppressed by appending
.Ql \ec
to the end of the string, as is done
by iBCS2 compatible systems.
Note that the
.Fl n
option as well as the effect of
.Ql \ec
are implementation-defined in
.St -p1003.1-2001
as amended by Cor.\& 1-2002.
For portability,
.Nm
should only be used if the first argument does not start with a hyphen
.Pq Ql "-"
and does not contain any backslashes
.Pq Ql "\e" .
If this is not sufficient,
.Xr printf 1
should be used.
.Pp
Most shells provide a builtin
.Nm
command which tends to differ from this utility
in the treatment of options and backslashes.
Consult the
.Xr builtin 1
manual page.
.Sh EXIT STATUS
.Ex -std
.Sh EXAMPLES
Special treatment of options and backslashes:
.Bd -literal -offset indent
$ /bin/echo "-hello\\tworld"
-hello\tworld
.Ed
.Pp
Avoid new line character:
.Bd -literal -offset indent
$ /bin/echo -n hello;/bin/echo world
helloworld
.Ed
.Pp
Or to achieve the same result:
.Bd -literal -offset indent
$ /bin/echo "hello\\c";/bin/echo world
helloworld
.Ed
.Sh SEE ALSO
.Xr builtin 1 ,
.Xr csh 1 ,
.Xr printf 1 ,
.Xr sh 1
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.1-2001
as amended by Cor.\& 1-2002.
.Sh HISTORY
The
.Nm
command appeared in
.At v2 .
.Sh CAVEATS
The
.Nm
command behaves differently with regards to the built-in
.Nm
shell command in a number of ways including escaped characters handling.
It also differs in behavior between different systems hence complicating writing
portable scripts.
It is advised to use the
.Xr printf 1
command to avoid these shortcomings.
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