ed

ed [options] [file]

The standard text editor. If the named file does not exist, ed creates it; otherwise, the existing file is opened for editing. As a line editor, ed is generally no longer used because vi and ex have superseded it. Some utilities, such as diff, continue to make use of ed. Encryption can be used only in the United States.

Options

-C

Same as -x, but assume file began in encrypted form.

-p string

Set string as the prompt for commands (default is *). The P command turns the prompt display on and off.

-s

Suppress character counts, diagnostics, and the ! prompt for shell commands.

-x

Supply a key to encrypt or decrypt file using crypt.