A VISTA command is ordinarily terminated by typing a RETURN, thus limiting the normal command length to one line of 80 characters. However, you can continue a command onto the next line by ending the current line of characters with the character. The last non-blank character must be a for your command to be extended. You will be prompted for the rest of the command with a colon on the next line. Example:
There is a limit to the length of a command permitted even when using the character, and that limit is 500 characters.