StreamManager | Recover Persisted Data from File

This isn't documented because you aren't supposed to read the data manually, I absolutely will point you to the read messages API to do this for you.

With that said, the header format is 32 bytes total, ending with the payload length:

+-----------+---------+-----------+--------------+---------+-----------+---------------+
| magicSeq  | version | relSeqNum | bytePosition |  crc       | timestamp | payloadLength |
|  3 bytes     | 1 byte   |  4 bytes       |  4 bytes.       | 8 bytes |  8 bytes      |  4 bytes             |
+-----------+---------+-----------+--------------+---------+-----------+---------------+

Thanks for suggesting the read_messages API. Would this API only work when called inside of a Greengrass component? Is there an API we can use without spinning up a Greengrass component?

Normally you'd need a component yes just to authenticate with Stream manager, but you can also disable authentication in Stream manager. STREAM_MANAGER_AUTHENTICATE_CLIENT https://docs.aws.amazon.com/greengrass/v2/developerguide/stream-manager-component.html#stream-manager-component-configuration

Ok thanks for that pointer - I will verify that. I have another follow-up question: It appears to me that the StreamManager persists the data regardless of whether the data is successfully exported, what's the intention behind that design? An alternative in my mind is to remove the successfully exported data, which will save storage space in the core device.