sdiff
|
After you've used
diff
for a while, the output is easy to read.
Sometimes, though, it's just easier to
see two files side-by-side.
The
sdiff
command does that.
(There's also a GNU version on the CD-ROM.)
Between the files, it prints
<
to point to lines that are only
in the first file,
>
for lines only in the second file, and
|
for lines that are in both, but different.
By default,
sdiff
shows all the lines in both files.
Here's a fairly bogus example that compares two files that contain
the output of
who
(
51.4
)
at different times: |
$
sdiff -w75 who1 who2
jake vt01 Sep 10 10:37 jake vt01 Sep 10 10:37
uunmv ttyi1i Sep 16 11:43 <
jerry ttyi1j Sep 15 22:38 jerry ttyi1j Sep 15 22:38
jake ttyp1 Sep 9 14:55 jake ttyp1 Sep 9 14:55
jake ttyp2 Sep 9 15:19 | ellen ttyp2 Sep 16 12:07
> carolo ttyp5 Sep 16 13:03
alison ttyp8 Sep 9 12:49 alison ttyp8 Sep 9 12:49
To see only lines that are different, use
-s
(silent):
$
sdiff -s -w75 who1 who2
2d1
uunmv ttyi1i Sep 16 11:43 <
5c4,5
jake ttyp2 Sep 9 15:19 | ellen ttyp2 Sep 16 12:07
> carolo ttyp5 Sep 16 13:03
The output lines are usually 130 characters long.
That's too long for 80-column-wide screens; if you can put your terminal
in 132-column mode or stretch your window, fine.
If you can't, use the
-w
option to set a narrower width, like
-w80
for 80-column lines;
sdiff
will show the first 37 characters
from each line (it doesn't write quite all 80 columns).
If you can set your printer to compressed type or have a very wide window,
use an option like
-w170
to get all of each line.
Article
28.6
explains a very useful feature of
sdiff
: building one file
interactively from two files you compare.