System information

You can reference an absolute line number by preceding any command by a number followed by
a colon, in the same format as the line number display. In this case, the ED program moves the
current line reference to the absolute line number, if the line exists in the current memory buffer.
The line denoted by the absolute line number must be in the memory buffer (see the A
command). Thus, the command
345:T
is interpreted as move to absolute 345, and type the line.
Absolute line numbers are produced only during the editing
process and are not recorded with the file. In particular, the
line numbers will change following a deleted or expanded section
of text.
You can also reference an absolute line number as a backward or forward distance from the
current line by preceding the absolute number by a colon. Thus, the command
:400T
is interpreted as type from the current line number through the line whose absolute number is
400. Combining the two line reference forms, the command
345::400T
is interpreted as move to absolute line 345, then type through absolute line 400. Absolute line
references of this sort can precede any of the standard ED commands.
Line numbering is controlled by the V (Verify Line Numbers) command. Line numbering can be
turned off by typing the -V command.
If the file to edit does not exist, ED displays the following message:
NEW FILE
To move text into the memory buffer, you must enter an i command before typing input lines and
terminate each line with a carriage return. A single CTRL-Z character returns ED to command
mode.
2.1 Introduction to ED CP/M Operating System Manual
2-6