3.3

F The Line Editor, ed
298
Saving Changes
The changes you make to a file are not saved immediately. This means you could quit (or
exit) ed without saving changes if necessary. You must use the Write command to save
modifications.
To save changes, type
w and press Enter. The line editor, ed, will respond by displaying the
file size, such as:
w
3624
n
The Write command is case-sensitive. If uppercase W is used, ed will append the modified
version of the file to the end of the original file version. This can quickly increase the file size
and result in redundancy. Always use the lowercase w.
Quitting ed
To exit the line editor, type q and press Enter. For instance:
w
3624
q
NRCS-A$
t
The Copy command copies the line specified, and inserts a copy after the target
location. For instance:
5t10 - Inserts a copy of line 5 below line 10. The copy becomes line 11. The
original line 11, if any, becomes line 12, and so forth.
20,30t50 - Inserts copies of lines 20 through 30 after line 50.
u
The Undo command is used to cancel the effects of the last editing command
entered. For instance:
1,5m$
u
In the above example, the user issues a command to move lines 1 through 5 to the
end of the file, then types u to undo that command.
Command Description & Examples (Continued)