Chapter 2. File Comparison And Merge

Command-Line Options

Comparing 2 files:

-   kdiff3 file1 file2
-

Merging 2 files:

-   kdiff3 file1 file2 -m
-   kdiff3 file1 file2 -o outputfile
-

Comparing 3 files:

-   kdiff3 file1 file2 file3
-

Merging 3 files:

-   kdiff3 file1 file2 file3 -m
-   kdiff3 file1 file2 file3 -o outputfile
-

- Note that file1 will be treated as - base of file2 and - file3. -

Special case: Files with the same name

-If all files have the same name but are in different directories, you can -reduce typework by specifying the filename only for the first file. E.g.: -

-   kdiff3 dir1/filename dir2 dir3
-

Commandline for starting a directory comparison or merge:

This is very similar, but now it's about directories.

-   kdiff3 dir1 dir2
-   kdiff3 dir1 dir2 -o destdir
-   kdiff3 dir1 dir2 dir3
-   kdiff3 dir1 dir2 dir3 -o destdir
-

For directory comparison and merge you can continue to read here.

Other command line options

To see all available command line options type

-kdiff3 --help
-

Example output:

-Options:
-  -m, --merge               Merge the input.
-  -b, --base file           Explicit base file. For compatibility with certain tools.
-  -o, --output file         Output file. Implies -m. E.g.: -o newfile.txt
-  --out file                Output file, again. (For compatibility with certain tools.)
-  --auto                    No GUI if all conflicts are auto-solvable. (Needs -o file)
-  --qall                    Don't solve conflicts automatically. (For compatibility...)
-  --L1 alias1               Visible name replacement for input file 1 (base).
-  --L2 alias2               Visible name replacement for input file 2.
-  --L3 alias3               Visible name replacement for input file 3.
-  -L, --fname alias         Alternative visible name replacement. Supply this once for every input.
-  --cs string               Override a config setting. Use once for every setting. E.g.: --cs "AutoAdvance=1"
-  --confighelp              Show list of config settings and current values.
-  --config file             Use a different config file.
-

The option --cs allows you to adjust a configuration value that is otherwise only adjustable via the configure dialogs. -But be aware that when KDiff3 then terminates the changed value will be stored along with the other settings. -With --confighelp you can find out the names of the available items and current values.

Via --config you can specify a different config file. When you often use KDiff3 -with completely different setups this allows you to easily switch between them.

Ignorable command line options

Many people want to use KDiff3 with some version control system. -But when that version control system calls KDiff3 using command line parameters that KDiff3 doesn't recognise, then KDiff3 terminates with an error. -The integration settings allow to specify command line parameters that should be ignored by KDiff3. -They will appear in the usage help like in this example:

-  --foo                     Ignored. (User defined.)
-

Command line options to ignore:: - A list of options, separated via semicolon ';'. When one of these options appears on the commandline, - then KDiff3 will ignore it and run without reporting an error. - (Default is "u;query;html;abort").

When this isn't enough, then it is recommended to write a shell script that does the option translation.