Documentation out of date in README.md

[reactive-firewall]

Looks like the integration tests usage and the directions in `README.md`` have diverged.

• design desision on CLI API
• refactor if needed
• Update documentation in README.md

[reactive-firewall]

The CLI is actually not the best way to use this kind of library so it should not be considered the full implementation. For testing though it is quite convenient.

CLI should work like so:

multicast (SAY|RECV|HEAR) [-h|--help] [--use-std] [--daemon] [--port PORT] [--iface IFACE] [--pipe|-m MESSAGE|--message MESSAGE] [--group BIND_GROUP] [--groups [JOIN_MCAST_GROUPS ...]]

the commands are SAY, RECV, and HEAR for the CLI and are analogus to send listen/accept and echo functions of a 1-to-1 connection.

SAY

The SAY command is used to send data messages via multicast diagrams.

• Note: the --daemon flag has no effect on the SAY command.

RECV

The RECV command is used to receive multicast diagrams by listening or "joining" a multicast group.

• if the --use-std flag is set the output is printed to the standard-output
• this command is purely for testing or interfacing with external components and not intended as a first-class API
• Note: If the --daemon flag is used the process will loop after reporting each diagram until canceled, it has no effect on the RECV command.

HEAR

The HEAR command is used to send data acknowledged messages via "HEAR" messages echoing select received multicast diagrams.

• while mostly a testing function it is possible to use HEAR as a proxy for other send/recv instances by using the --daemon flag
• note this will use the same port for sends and receives and can lead to data loss if less than two groups are used.
• If more than one group is used via the --groups flag then all but the bind group (via --group) will be echoed to the bind group.

[reactive-firewall]

ℹ️ see #20 for exit-codes.