Merge Directories dir1/ ├─ file_a.txt └─ file_b.txt dir2/ ├─ file_a.txt └─ file_c.txt result/ ├─ file_a.txt ├─ file_b.txt └─ file_c.txt dir1 + dir2 = result file_a is overwritten file_b is not changed file_c is added dir1 is overwritten with the result.