diff --git a/src/timer.c b/src/timer.c
index 9408fe0..155e78f 100644
--- a/src/timer.c
+++ b/src/timer.c
@@ -25,6 +25,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/file.h>
 #include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
@@ -490,21 +491,29 @@ static void int_timer_init()
 
 void int_io_open(int fd)
 {
+  DBPRINT(("int_io_open %d\n", fd));
 #ifdef DOS
 /* would turn on DOS kbd signal handler here */
-#elseif defined(O_ASYNC)
-  DBPRINT(("int_io_opening %d\n", fd));
+#elif defined(O_ASYNC)
   if (fcntl(fd, F_SETOWN, getpid()) == -1) perror("fcntl F_SETOWN error");
   if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_ASYNC) == -1) perror("fcntl F_SETFL on error");
+#elif defined(FASYNC) && defined(FNDELAY)
+  if (fcntl(fd, F_SETOWN, getpid()) == -1) perror("fcntl F_SETOWN error");
+  if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | FNDELAY | FASYNC) == -1) perror("fcntl F_SETFL on error");
+#else
+#warning "No async i/o can be enabled - investigate and remedy this"
 #endif
 }
 
 void int_io_close(int fd)
 {
+  DBPRINT(("int_io_close %d\n", fd));
 #ifdef DOS
 /* Turn off signaller here */
-#elseif defined(O_ASYNC)
+#elif defined(O_ASYNC)
   if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) & ~O_ASYNC) == -1) perror("fcntl_F_SETFL off error");
+#elif defined(FASYNC) && defined(FNDELAY)
+  if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) & ~(FNDELAY | FASYNC)) == -1) perror("fcntl F_SETFL off error");
 #endif
 }