The Legato application framework is designed to solve many difficult problems surrounding updating software on devices that are operating in the field:

Atomic update of libraries, executables, resource files, and configuration settings.
Autonomous recovery from failed update attempts (e.g., due to power loss or connection loss).
Autonomous roll-back when newly updated software fails.
Reduce flash consumption by sharing read-only app files that are the same in different software versions.

Software updates are primarily carried out by the Update Daemon but, the Supervisor and start-up code also have a role to play in rolling-back when updates fail.

See

Update Process
Update Pack Format
Software Update
update target tool

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