echo(1) — Commands
OSF
NAME
echo − Writes its arguments to standard output
SYNOPSIS
echo [string ...]
The echo command writes the specified string to standard output.
DESCRIPTION
The arguments are separated by spaces and a newline character follows the last string. Use echo to produce diagnostic messages in command files and to send data into a pipe.
The echo command described here is the program /bin/echo. Both csh and sh contain built-in echo subcommands, which do not necessarily work in the same way as the /bin/echo command.
The echo command recognizes the following special characters:
\bDisplays a backspace character.
\cSuppresses the newline character.
\fDisplays a formfeed character.
\nDisplays a newline character.
\rDisplays a carriage-return character.
\tDisplays a tab character.
\vDisplays a vertical tab.
\\Displays a backslash character.
\numberDisplays an 8-bit character whose value is the 1-, 2- or 3-digit octal number, number. The first digit of number must be a 0 (zero).
EXAMPLES
1.To write a message to standard output, enter:
echo Please insert diskette . . .
2.To display a message containing special characters as listed in DESCRIPTION, enclose the message in quotes, as follows:
echo "\n\n\nI’m at lunch.\nI’ll be back at 1 p.m."
This skips three lines and displays the message:
I’m at lunch.
I’ll be back at 1 p.m.
Note that you must enclose the message in quotation marks if it contains escape sequences such as \n. Otherwise, the shell treats the \ (backslash) as an escape character. The above command, entered without the quotes, results in the following output:
nnnI’m at lunch.nI’ll be back at 1 p.m.
3.To use echo with pattern-matching characters, enter:
echo The back-up files are: ∗.bak
This displays the message The back-up file are: and then displays the filenames in the current directory ending with .bak.
4.To add a single line of text to a file, enter:
echo Remember to set the shell search path to $PATH. >>notes
This adds the message to the end of the file notes after the shell substitutes the value of the PATH shell variable.
5.To write a message to the standard error output (sh only), enter:
echo Error: file already exists. >&2
Use this in shell procedures to write error messages. If the >&2 is omitted, then the message is written to the standard output.