Simple Addresses:
0          Head of file.
$          End of file.
#n         Jump to character n.
n          Jump to line n.
/regexp/   First forward occurence of rexexp.
?regexp?   First backward occurence of regexp.
.          Dot.
,          The mark in the file (see k command).
"regexp"   Preceding simple address is in the file
           referred to by regexp.

Compound Addresses:
a1+a2    a2 relative to the end of a1.
a1-a2    a2 backwards from start of a2.
a1,a2    The substring from start of a1 to end of
         a2.
a1;a2    Like a1,a2, but a2 relative to a1.

+ and - bind more tightly than , or ;.
Useful idioms: a1+- select line containing a1;
               0/regexp/ find first match;
               ./regexp/// second occurrence;
               .,/regexp/ extends dot.

Commands:
a/text/        Insert text after range.
c              As a, but replace text.
i              Insert before range.
d              Delete range.
s/regexp/text/ Substitute text for first match.
               & stands for the string that matched.
               \d where d is a number offsets within &.
               s2/x/y/ replaces second match.
               s/x/y/g replaces all matches.

p              Print text in range.
=              Print line and char of range.
=#             Print char of range.


b file-list    Set current file to first listed file
               already open. List may be <command.
B file-list    As b, but open unopened files in list.
n              Print menu of files.
               ' or blank  : modified or clean.
               - or + or * : unread or read or
                             multiple windows
                             viewing.
               . or blank  : current file.
D file-list    Close files. D alone closes current.


e filename  Replace file with contents of
            filename.
r filename  Replace range with contents of
            filename.
w filename  Write the range (def. 0,$) to
            filename.
f filename  Set the file name and print its new
            menu entry.


< command   Replace range with stdout of command.
> command   Replace range with stdin of command.
| command   Pipe range to stdin, stdio to range.
! command   Run command.
When command is omitted, the last shell command will
be substituted.

Loops and Conditionals:
x/regexp/ command    Run command on each match in range.
y/regexp/ command    As X but on all non-matches.
X/regexp/ command    For each file matching, command.
Y/regexp/ command    As X on non-matches.
g/regexp/ command    If range contains match, run.
v/regexp/ command    Inverted g.

Misc:
k    Set mark to range.
q    Quit.
u n  Undo last n top-level commands in current file.
     -n is redo.

Commands may be grouped within {}. They must appear
on seperate lines. Changes by one command are not
visible to others.

Graphical mode:
Esc selects text typed since last mouse button press.
Button 3 opens the window ops. menu.
Button 1 changes the selection.
Button 2 opens the editing menu.
   <rio>   Exchange snarf buffer with rio.
   /regexp Search for next occurrence of last regexp
           typed in a command.