int xloc = 100;
int yloc = 100;

char * sendBuf = malloc(100);

char * toSend = "LOC";

strcpy(toSend,sendBuf);
itoa(xloc,sendBuf[strlen(toSend));

OR

sprintf(sendBuf, "%s,%d",toSend,xloc);

iprintf("%s",sendBuf);

send(my_socket, sendBuf, strlen(sendBuf), 0);