tcpSendReceive host program reports recv failure

Other Parts Discussed in Thread: EK-TM4C1294XL

Running the pre-compiled tcpSendReceive from tirtos_tivac_2_00_01_23 on a Linux host, communicating with the TCP Echo example running on a EK-TM4C1294XL, it was found that the the tcpSendReceive host program would report a recv failure after a variable number of interations. e.g.:

[Mr_Halfword@CentOS-Desktop ~]$  /opt/ti/ti_ccs6_0/tirtos_tivac_2_00_01_23/packages/examples/tools/tcpSendReceive 192.168.0.4 1000 1 -s100
Starting test with a 100 uSec delay between transmits
[id 1] count = 1000, time = 1
[id 1] count = 2000, time = 2
[id 1] count = 3000, time = 3
[id 1] count = 4000, time = 4
[id 1] count = 5000, time = 6
[id 1] count = 6000, time = 7
[id 1] count = 7000, time = 8
[id 1] stopping test. recv returned 512

The problem is the following in the tirtos_tivac_2_00_01_23/packages/examples/tools/tcpSendReceive.c source file which expects recv() to always return buffSize number of bytes:

        bytes_read = recv(sockfd, buffer, buffSize, 0);
        if (bytes_read != buffSize) {
            printf("[id %d] stopping test. recv returned %d\n", id, bytes_read);
            status = EXIT_FAILURE;
            goto QUIT;
        }

In fact recv returns the number of available bytes in the TCP socket (which after-all is a byte stream). i.e.
tcpSendReceive.c should be changed to call recv in a loop:

    int total_bytes_read;

    ...

        total_bytes_read = 0;
        while (total_bytes_read < buffSize)
        {
            bytes_read = recv(sockfd, &buffer[total_bytes_read], buffSize - total_bytes_read, 0);
            if (bytes_read <= 0)
            {
                printf("[id %d] stopping test. recv returned %d\n", id, bytes_read);
                status = EXIT_FAILURE;
                goto QUIT;
            }
            total_bytes_read += bytes_read;
        }

With this change the tcpSendReceive program then ran reliably.