www.delorie.com/gnu/docs/diffutils/diff_13.html

search

	Buy GNU books!

Comparing and Merging Files

2.2.1 Detailed Description of Normal Format

The normal output format consists of one or more hunks of differences; each hunk shows one area where the files differ. Normal format hunks look like this:

change-command < from-file-line < from-file-line... --- > to-file-line > to-file-line...

There are three types of change commands. Each consists of a line number or comma-separated range of lines in the first file, a single character indicating the kind of change to make, and a line number or comma-separated range of lines in the second file. All line numbers are the original line numbers in each file. The types of change commands are:

`lar'

Add the lines in range r of the second file after line l of the first file. For example, `8a12,15' means append lines 12--15 of file 2 after line 8 of file 1; or, if changing file 2 into file 1, delete lines 12--15 of file 2.

`fct'

Replace the lines in range f of the first file with lines in range t of the second file. This is like a combined add and delete, but more compact. For example, `5,7c8,10' means change lines 5--7 of file 1 to read as lines 8--10 of file 2; or, if changing file 2 into file 1, change lines 8--10 of file 2 to read as lines 5--7 of file 1.

`rdl'

Delete the lines in range r from the first file; line l is where they would have appeared in the second file had they not been deleted. For example, `5,7d3' means delete lines 5--7 of file 1; or, if changing file 2 into file 1, append lines 5--7 of file 1 after line 3 of file 2.