echo invocation (GNU Coreutils 9.0)
Next: printf invocation, Up: Printing text [Contents][Index]
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), ifnnn
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), ifnnn
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.
Next: printf invocation, Up: Printing text [Contents][Index]