Messages are usually removed from ports with the GetMsg() function. This function removes the next message at the head of the port queue and returns a pointer to it. If there are no messages in a port, this function returns a zero. The example below illustrates the use of GetMsg() to print the contents of all messages in a port: while (xymsg = GetMsg(xyport)) printf("x=%ld y=%ld\n", xymsg->xy_X, xymsg->xy_Y); Certain messages may be more important than others. Because ports impose FIFO ordering, these important messages may get queued behind other messages regardless of their priority. If it is necessary to recognize more important messages, it is easiest to create another port for these special messages.