Linux c socket TCP_NODELAY fast send

If you want send packet immediately. Try this

         int flag = 1;
         int result = setsockopt(sock,            /* socket affected */
                                 IPPROTO_TCP,     /* set option at TCP level */
                                 TCP_NODELAY,     /* name of option */
                                 (char *) &flag,  /* the cast is historical
                                                         cruft */
                                 sizeof(int));    /* length of option value */
         if (result < 0)
            ... handle the error ...


leo friendly note: TCP_NODELAY is in