c- recvfrom error 22

Question

Okay first here is the code:

int recvMast_sock;
struct sockaddr_in serv_addr, cli_addr;
socklen_t cli_len;
if ((recvMast_sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
  {
    critErr("listen:socket=");
  }

fillSockaddrAny(&serv_addr, UDP_NODE_LISTEN_PORT);// fills the sockaddr_in works fine elsewhere

if ((bind(recvMast_sock, (struct sockaddr*) &serv_addr, sizeof serv_addr)) < 0)
  {
    critErr("listen:bind recv_mast_sock:");
  }
recvReturn_i = recvfrom(recvMast_sock, &recvBuff[0], (size_t)1, 0, (struct   sockaddr*) &cli_addr, &cli_len);
if(recvReturn_i <0)
        printf("recv error%d\n",errno);

critErr is a function to handle errors which also includes a print of the error and an exit.

This runs in a thread, if this is of any relevance. If I compile and run this on a Zedboard (ZYNQ-7000 SoC) which has an ARM Cortex A9 and Linaro Linux (based on precise Ubuntu). It prints error 22 but still has the received value in recvBuff[0].

Running this in my VM with xubuntu it works fine.

Error 22 equals EINVAL which is described as Invalid argument.

In the manpage of recvfrom(2) it states EINVAL means that the MSG_OOB flag is set but I don't use any flags (passing 0).

Before leaving on friday I started an apt-get upgrade because I hope it is a faulty library or something like this. I can check back at monday but maybe someone here has another idea what is wrong.

Answer 1

This was not caused by the OS or the architecture. The function was not called on the x86-system because of a blocked mutex. So I didn't got the error there.

The problem was that I passed the socket to this function from 'main' (which i did not state in the question because I thought it was irrelevant, my bad...) In 'main' I used it and used it in this function. Even though it was mutually exclusive, there was this error.

Remy's answer was also relevant but not a solution to the problem. Not setting cli_len beforehand just leads to a cut of sockaddr if its too small. No error was generated for that.