Receive byte across link cable

#include <gb/gb.h>
#include <stdio.h>

void main(void){
    while(1){//the program is in a while loop so it keeps checking again and again for a byte

      printf("Receiving...");

      /*look for a byte being sent through the link cable
      if there is a byte set _io_in to the value of the byte
      */
      receive_byte();

      /* Wait for IO completion... */
      while(_io_status == IO_RECEIVING){;}

      if(_io_status == IO_IDLE){
       printf("Received:\n%d\n", (int)_io_in);
}
      else{
      printf("error: %d\n", _io_status);
}
}
}