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Confusing parameter documentation in mtp_init_client #551

Open Misamag opened 9 months ago

Misamag commented 9 months ago

In function mtp_init_client, there is a mtp_dest_host parameter. The doc is multicast ip address where the sensor should send data.

As I can see from the code, it's rather the local ip address of the interface which is used to join the mutlicast group which is defined in the config parameter. If it's empty, the OS will automatically all (?) interfaces.

twslankard commented 9 months ago

Thanks for the report @Misamag - I'll make sure we fix the documentation.

Best Regards,

Tom Staff Engineer Ouster Inc.

twslankard commented 9 months ago

After double-checking the code, it looks like mtp_dest_host specifies the address of the interface used to join the multicast group.

However, any interface will be used[1] if mtp_dest_host is empty (which as you've probably seen in the code sets the address to INADDR_ANY in an ip_mreq structure passed to setsockopt to join the multicast group.)

[1] https://man7.org/linux/man-pages/man7/ip.7.html