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15.1 echo: Print a line of text

echo writes each given string to standard output, with a space between each and a newline after the last one. Synopsis:

echo [option]… [string]…

Due to shell aliases and built-in echo functions, using an unadorned echo interactively or in a script may get you different functionality than that described here. Invoke it via env (i.e., env echo …) to avoid interference from the shell.

Due to historical and backwards compatibility reasons, certain bare option-like strings cannot be passed to echo as non-option arguments. It is therefore not advisable to use echo for printing unknown or variable arguments. The printf command is recommended as a more portable and flexible replacement for tasks historically performed by echo. See printf invocation.

The program accepts the following options. Also see Common options. Options must precede operands, and the normally-special argument ‘--’ has no special meaning and is treated like any other string.

-n

Do not output the trailing newline.

-e

Enable interpretation of the following backslash-escaped characters in each string:

\a

alert (bell)

\b

backspace

\c

produce no further output

\e

escape

\f

form feed

\n

newline

\r

carriage return

\t

horizontal tab

\v

vertical tab

\\

backslash

\0nnn

the eight-bit value that is the octal number nnn (zero to three octal digits), if nnn is a nine-bit value, the ninth bit is ignored

\nnn

the eight-bit value that is the octal number nnn (one to three octal digits), if nnn is a nine-bit value, the ninth bit is ignored

\xhh

the eight-bit value that is the hexadecimal number hh (one or two hexadecimal digits)

-E

Disable interpretation of backslash escapes in each string. This is the default. If -e and -E are both specified, the last one given takes effect.

If the POSIXLY_CORRECT environment variable is set, then when echo’s first argument is not -n it outputs option-like arguments instead of treating them as options. For example, echo -ne hello outputs ‘-ne hello’ instead of plain ‘hello’. Also backslash escapes are always enabled. Note to echo the string ‘-n’, one of the characters can be escaped in either octal or hexadecimal representation. For example, echo -e '\x2dn'.

POSIX does not require support for any options, and says that the behavior of echo is implementation-defined if any string contains a backslash or if the first argument is -n. Portable programs should use the printf command instead. See printf invocation.

An exit status of zero indicates success, and a nonzero value indicates failure.


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