Diff option to get line number

Shell Programming and Scripting
1

Hi,

I am using the below command to get the diff output of two files.
Here in the output file, I wish to add line number in front of each line starting position.
Please suggest the diff options or some command line utilities.

diff -y file1.txt file2.txt --width=300 > diff_f1_f2_300.txt

Thanks in advance.
Manimuthu

2

Not clear! But, mayhap,

diff -y file1.txt file2.txt --width=300 | nl > diff_f1_f2_300.txt

?

1 Like
3

Or maybe this?

file1:

one
two
three

file2:

one
two
four

and

$ diff --old-line-format="%5dn< %L" --new-line-format="%5dn> %L" --unchanged-line-format="" file1 file2
    3< three
    3> four

or

$ diff --old-line-format="%5dn< %L" --new-line-format="%5dn> %L" --unchanged-line-format="%5dn= %L" file1 file2
    1= one
    2= two
    3< three
    3> four

You can play with the formats to get the results you need. Note: The formatting options are GNU extensions to the diff command.

3 Likes
4

Thanks, Here what is the mean for "%5dn< %L" ?

5

%5dn prints the line number with a standard printf like format of %5d (numeric, 5 characters wide with leading blanks).

< or > are literal strings.

%L is substituted by the line content.

See also the diff man-page

1 Like
6

Note: hergp's really good answer will only work with GNU diff - usually what you have with linux.