unison

Bidirectional file synchronisation tool. More information: https://www.cis.upenn.edu/~bcpierce/unison/download/releases/stable/unison-manual.html.

• Sync two directories (creates log first time these two directories are synchronized):
  unison {{path/to/directory_1}} {{path/to/directory_2}}
• Automatically accept the (non-conflicting) defaults:
  unison {{path/to/directory_1}} {{path/to/directory_2}} -auto
• Ignore some files using a pattern:
  unison {{path/to/directory_1}} {{path/to/directory_2}} -ignore {{pattern}}
• Show documentation:
  unison -doc {{topics}}