If you start Meld from the command line, you can tell it what to do when it starts.
For a two- or three-way Meld with meld file1 file2 or meld file1 file2 file3 respectively., start
For a two- or three-way Meld with meld dir1 dir2 or meld dir1 dir2 dir3., start
You can start a meld . would start a version control view of the current directory.comparison by just giving a single argument; if that file or directory is managed by a , it will start a version control comparison on that argument. For example,
Run meld --help for a list of all command line options.