RTOS/CC3120MOD: Receive whole Messages with sl_Recv

Marvin Gnad

Part Number: CC3120MOD

Tool/software: TI-RTOS

Hello,

I want to receive whole packages with sl_Recv, but in the documentation here: dev.ti.com/.../group___socket.html
It says flags are not supported.

I want to do something similar like this:

recv(socket_rcv, bufferRx, PACKETSIZE, MSG_WAITALL);

I don't know the exact packetsize so this is no option for me.

Currently i have no idea how to move around this problem.

Greetings,
Marvin

over 6 years ago

0 Jan D over 6 years ago

Guru 79985 points

Hi Marvin,

This API if for TCP communication and from this reason there is nothing like a "whole packet". You can read only data available in internal buffers. By len parameter you specify size of your buffer to avoid overflow of your buffer.

Jan

0 Marvin Gnad over 6 years ago in reply to Jan D

Intellectual 455 points

Hi Jan,

I misunderstood the "MSG_WAITALL" flag. And thought it returns after "a full package" but like you already mentioned there is nothing like this in TCP Communication.

I solved the initial problem i had in another way.

But to get something similar like the "MSG_WAITALL" flag I wrote this code:

		while (len > 0)
		{
			recv_size = len;
			
			rc = sl_Recv(my_socket, buffer + recvLen, recv_size, 0);
			len = len - rc;
			if (rc < 0)
			{
				recvLen = -1;
				break;
			}
			else if (rc == 0)
			{
				recvLen = 0;
				break;
			}
			else if (rc > 0)
			{
				recvLen += rc;
			}
		}

Thanks,

Marvin

0 Hnz over 6 years ago in reply to Marvin Gnad

Guru 39650 points

Hi Marvin,

Yes, this is one of the possible ways, in case of that you want read exact number of bytes from socket.

Jan

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RTOS/CC3120MOD: Receive whole Messages with sl_Recv