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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.

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.

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 can use the printf command if they need to omit trailing newlines or output control characters or backslashes. See printf invocation.

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


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