Narrowing Top Editing Binary Files
Two-column mode lets you conveniently edit two side-by-side columns of text. It uses two side-by-side windows, each showing its own buffer.
There are three ways to enter two-column mode:
F2 2 or C-x 6 2
|
Enter two-column mode with the current buffer on the left, and on the
right, a buffer whose name is based on the current buffer's name
( This command is appropriate when the current buffer is empty or contains just one column and you want to add another column. |
F2 s or C-x 6 s
|
Split the current buffer, which contains two-column text, into two
buffers, and display them side by side ( This command is appropriate when you have a buffer that already contains two-column text, and you wish to separate the columns temporarily. |
F2 b buffer RET
C-x 6 b buffer RET
|
Enter two-column mode using the current buffer as the left-hand buffer,
and using buffer buffer as the right-hand buffer
( |
F2
s or C-x 6 s looks for a column separator, which
is a string that appears on each line between the two columns. You can
specify the width of the separator with a numeric argument to
F2
s; that many characters, before point, constitute the
separator string. By default, the width is 1, so the column separator
is the character before point.
When a line has the separator at the proper place, F2
s
puts the text after the separator into the right-hand buffer, and
deletes the separator. Lines that don't have the column separator at
the proper place remain unsplit; they stay in the left-hand buffer, and
the right-hand buffer gets an empty line to correspond. (This is the
way to write a line that ``spans both columns while in two-column
mode'': write it in the left-hand buffer, and put an empty line in the
right-hand buffer.)
The command C-x 6 RET
or F2
RET
(2C-newline
) inserts a newline in each of the two buffers at
corresponding positions. This is the easiest way to add a new line to
the two-column text while editing it in split buffers.
When you have edited both buffers as you wish, merge them with
F2
1 or C-x 6 1 (2C-merge
). This copies the
text from the right-hand buffer as a second column in the other buffer.
To go back to two-column editing, use F2
s.
Use F2
d or C-x 6 d to dissociate the two buffers,
leaving each as it stands (2C-dissociate
). If the other buffer,
the one not current when you type F2
d, is empty,
F2
d kills it.