Handling send e recv errors in C

Question

I'm new in C language and I'm writing a TCP server

// create a socket, bind and listen
while(1) {
 accept:
 int conn_sock = accept(...);
 // here some recv and send calls
}

I want to prevent server shutdown if ECONNRESET or EINTR occurred. If one of this errors occur while sending or receiving data I want to go to accept (want to go to accept label if accept() fails for some reason as well).

If I don't catch these errors my server stops to work if a client close the connection.

How can I catch these errors and go back to accept to establish a connection with another client?

Answer 1

On error accept() returns -1. The error's reason then can be read from errno.

One possible approach so would be:

  int errno_accept;
  while (1)
  {
    errno_accept = 0;
    int accepted_socket = accept(...);
    if (-1 == accepted_socket)
    {
      errno_accept = errno;
      switch(errno_accept)
      {
        case EINTR:
        case ECONNRESET: /* POSIX does *not* define this value to be set 
                       by a failed call to accept(), so this case is useless. */

        default:
          /* Catch unhandled values for errno here. */

          break; /* Treat them as fatal. */

        ...
  } /* while (1) */

  if (0 != errno_accept)
  {
    /* Handle fatal error(s) here. */
  }