Options to diff3

Below is a summary of all of the options that GNU diff3 accepts. Multiple single letter options (unless they take an argument) can be combined into a single command line argument.

-a

--text

Treat all files as text and compare them line-by-line, even if they do not appear to be text. See Binary.

-A

--show-all

Incorporate all unmerged changes from older to yours into mine, surrounding conflicts with bracket lines. See Marking Conflicts.

--diff-program=program

Use the compatible comparison program program to compare files instead of diff.

-e

--ed

Generate an ed script that incorporates all the changes from older to yours into mine. See Which Changes.

-E

--show-overlap

Like -e, except bracket lines from overlapping changes' first and third files. See Marking Conflicts. With -E, an overlapping change looks like this:

<<<<<<< mine
lines from mine
=======
lines from yours
>>>>>>> yours

--help

Output a summary of usage and then exit.

-i

Generate w and q commands at the end of the ed script for System V compatibility. This option must be combined with one of the -AeExX3 options, and may not be combined with -m. See Saving the Changed File.

-L label

--label=label

Use the label label for the brackets output by the -A, -E and -X options. This option may be given up to three times, one for each input file. The default labels are the names of the input files. Thus diff3 -L X -L Y -L Z -m A B C acts like diff3 -m A B C, except that the output looks like it came from files named X, Y and Z rather than from files named A, B and C. See Marking Conflicts.

-m

--merge

Apply the edit script to the first file and send the result to standard output. Unlike piping the output from diff3 to ed, this works even for binary files and incomplete lines. -A is assumed if no edit script option is specified. See Bypassing ed.

-T

--initial-tab

Output a tab rather than two spaces before the text of a line in normal format. This causes the alignment of tabs in the line to look normal. See Tabs.

-v

--version

Output version information and then exit.

-x

--overlap-only

Like -e, except output only the overlapping changes. See Which Changes.

-X

Like -E, except output only the overlapping changes. In other words, like -x, except bracket changes as in -E. See Marking Conflicts.

-3

--easy-only

Like -e, except output only the nonoverlapping changes. See Which Changes.