freemodbus library how to send a parcel?

Question

C++ / C#

I urgently need to connect my device over the network, I read everything about modbus rtu, I found a free library, I understood how to configure the protocol, but I did not find how to send my array of bytes to the master's request. It's the first time I'm doing something like this. If anyone has experience, leave an email, I won’t get much.

Answer 1

The byte array can be read via queues or via files (Modbus commands 0x18 and 0x14). Neither freemodbus can do either. I see two solutions:
1. Add an extension for FIFO on top of the library.
2. Pass the array through the function "Read Input Registers (0x04)"
What size of the array is expected and is it known at the time of the request?