.TH DIFF3 1 "22sep1993" "GNU Tools" "GNU Tools"

.SH NAME

diff3 \- find differences between three files

.SH SYNOPSIS

.B diff3

[options] mine older yours

.SH DESCRIPTION

The

.I diff3

command compares three files and outputs descriptions

of their differences.

The files to compare are

.IR mine ,

.IR older ,

and

.IR yours .

At most one of these three file names may be

.BR \- ,

which tells

.I diff3

to read the standard input for that file.

.SS Options

Below is a summary of all of the options that GNU

.I diff3

accepts.  Multiple single letter options (unless they take an argument)

can be combined into a single command line argument.

.TP

.B \-a

Treat all files as text and compare them line-by-line, even if they

do not appear to be text.

.TP

.B \-A

Incorporate all changes from

.I older

to

.I yours

into

.IR mine ,

surrounding all conflicts with bracket lines.

.TP

.B \-B

Old behavior of -A.  Shows non-conflicts.

.TP

.B \-e

Generate an

.I ed

script that incorporates all the changes from

.I older

to

.I yours

into

.IR mine .

.TP

.B \-E

Like

.BR \-e ,

except bracket lines from overlapping changes' first

and third files.

With

.BR \-e ,

an overlapping change looks like this:

.sp

.nf

<<<<<<< \fImine\fP

lines from \fImine\fP

=======

lines from \fIyours\fP

>>>>>>> \fIyours\fP

.fi

.TP

.B \-\-ed

Generate an

.I ed

script that incorporates all the changes from

.I older

to

.I yours

into

.IR mine .

.TP

.B \-\-easy\-only

Like

.BR \-e ,

except output only the nonoverlapping changes.

.TP

.B \-i

Generate

.B w

and

.B q

commands at the end of the

.I ed

script for System V compatibility.  This option must be combined with

one of the

.B \-AeExX3

options, and may not be combined with

.BR \-m .

.TP

.B \-\-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.

.TP

.BI "\-L " label

.ns

.TP

.BI \-\-label= label

Use the label

.I label

for the brackets output by the

.BR \-A ,

.B \-E

and

.B \-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

.B "diff3 \-L X \-L Y \-L Z \-m A B C"

acts like

.BR "diff3 \-m A B C ,

except that the output looks like it came from

files named

.BR X ,

.B Y

and

.B Z

rather than from files

named

.BR A ,

.B B

and

.BR C .

.TP

.B \-m

.br

.ns

.TP

.B \-\-merge

Apply the edit script to the first file and send the result to standard

output.  Unlike piping the output from

.I diff3

to

.IR ed ,

this

works even for binary files and incomplete lines.

.B \-A

is assumed

if no edit script option is specified.

.TP

.B \-\-overlap\-only

Like

.BR \-e ,

except output only the overlapping changes.

.TP

.B \-\-show\-all

Incorporate all unmerged changes from

.I older

to

.I yours

into

.IR mine ,

surrounding all overlapping changes with bracket lines.

.TP

.B \-\-show\-overlap

Like

.BR \-e ,

except bracket lines from overlapping changes' first

and third files.

.TP

.B \-T

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.

.TP

.B \-\-text

Treat all files as text and compare them line-by-line, even if they

do not appear to be text.

.TP

.B \-v

.br

.ns

.TP

.B \-\-version

Output the version number of

.IR diff3 .

.TP

.B \-x

Like

.BR \-e ,

except output only the overlapping changes.

.TP

.B \-X

Like

.BR \-E ,

except output only the overlapping changes.

In other words, like

.BR \-x ,

except bracket changes as in

.BR \-E .

.TP

.B \-3

Like

.BR \-e ,

except output only the nonoverlapping changes.

.SH SEE ALSO

cmp(1), comm(1), diff(1), ed(1), patch(1), sdiff(1).

.SH DIAGNOSTICS

An exit status of 0 means

.I diff3

was successful, 1 means some

conflicts were found, and 2 means trouble.