echo command

15.1 'echo': Print a line of text
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'echo' writes each given STRING to standard output, with a space
between each and a newline after the last one. Synopsis:

echo [OPTION]... [STRING]...

The program accepts the following options. Also see *Note 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'
suppress trailing newline

'\f'
form feed

'\n'
new line

'\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)

'\NNN'
the eight-bit value that is the octal number NNN (one to
three octal digits)

'\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'.

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. *Note printf invocation::.

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