diff --git a/src/initdsp.c b/src/initdsp.c
index 41bc8dc..4e2ed04 100644
--- a/src/initdsp.c
+++ b/src/initdsp.c
@@ -108,8 +108,8 @@ int oldred[2], oldgreen[2], oldblue[2];
 #endif /* DISPLAYBUFFER */
 #endif /* NOPIXRECT */
 
-int LispWindowFd;
-int FrameBufferFd;
+int LispWindowFd = -1;
+int FrameBufferFd = -1;
 
 int displaywidth, displayheight, DisplayRasterWidth, DisplayType;
 int DisplayByteSize;
diff --git a/src/initkbd.c b/src/initkbd.c
index 07c960e..ce9da16 100644
--- a/src/initkbd.c
+++ b/src/initkbd.c
@@ -123,7 +123,7 @@ extern struct screen LispScreen;
 #endif /* SUNDISPLAY */
 
 extern int LispWindowFd;
-int LispKbdFd;
+int LispKbdFd = -1;
 extern int errno;
 
 /*   for debug    */
diff --git a/src/keyevent.c b/src/keyevent.c
index 3d03610..35fda58 100644
--- a/src/keyevent.c
+++ b/src/keyevent.c
@@ -124,11 +124,11 @@ extern fd_set LispIOFds;
 fd_set LispReadFds;
 int XNeedSignal = 0; /* T if an X interrupt happened while XLOCK asserted */
 
+extern int LogFileFd;
+
 #ifdef NOETHER
-extern u_int LogFileFd;
 #else
 extern int ether_fd;
-extern u_int LogFileFd;
 #endif /* NOETHER */
 
 extern DLword *DisplayRegion68k;
@@ -316,7 +316,7 @@ getmore:
       */
 
 #ifdef SUNDISPLAY
-    if (FD_ISSET(LispWindowFd, &rfds)) {
+    if (LispWindowFd >= 0 && FD_ISSET(LispWindowFd, &rfds)) {
       /* #endif */
       while (input_readevent(LispWindowFd, &event) >= 0) {
         /*if(!kb_event( &event )) {goto getmore;};*/
@@ -341,19 +341,19 @@ getmore:
 
 #ifdef NOETHER
 #else
-    if (FD_ISSET(ether_fd, &rfds)) { /* Raw ethernet (NIT) I/O happened, so handle it. */
+    if (ether_fd >= 0 && FD_ISSET(ether_fd, &rfds)) { /* Raw ethernet (NIT) I/O happened, so handle it. */
       DBPRINT(("Handling enet interrupt.\n\n"));
       check_ether();
     }
 #endif /* NOETHER */
 
 #ifdef RS232
-    if (FD_ISSET(RS232C_Fd, &rfds) || (RS232C_remain_data && rs232c_lisp_is_ready()))
+    if (RS232C_Fd >= 0 && (FD_ISSET(RS232C_Fd, &rfds) || (RS232C_remain_data && rs232c_lisp_is_ready())))
       rs232c_read();
 #endif /* RS232 */
 
 #ifdef LOGINT
-    if (FD_ISSET(LogFileFd, &rfds)) { /* There's info in the log file.  Tell Lisp to print it. */
+    if (LogFileFd >= 0 && FD_ISSET(LogFileFd, &rfds)) { /* There's info in the log file.  Tell Lisp to print it. */
       flush_pty();          /* move the msg(s) to the log file */
 
       ((INTSTAT *)Addr68k_from_LADDR(*INTERRUPTSTATE_word))->LogFileIO = 1;
diff --git a/src/osmsg.c b/src/osmsg.c
index bf7f015..3166202 100644
--- a/src/osmsg.c
+++ b/src/osmsg.c
@@ -64,7 +64,7 @@ int log_id;
 int previous_size;
 int logChanged; /* T if log file has changed since last READ */
                 /* Set by flush_pty, to avoid the stat call  */
-u_int LogFileFd;
+int LogFileFd = -1;
 extern fd_set LispReadFds;
 
 /************************************************************************/
diff --git a/src/rs232c.c b/src/rs232c.c
index 8790f2e..6f136af 100644
--- a/src/rs232c.c
+++ b/src/rs232c.c
@@ -29,7 +29,7 @@ static DLword *RS232CGetCSB, *RS232CPutCSB;
  * File descriptor
  */
 extern fd_set LispReadFds;
-int RS232C_Fd;
+int RS232C_Fd = -1;
 
 int RS232C_remain_data;
 static char *RS232C_Dev;
diff --git a/src/timer.c b/src/timer.c
index b50ba46..dba2307 100644
--- a/src/timer.c
+++ b/src/timer.c
@@ -460,7 +460,7 @@ int TIMER_INTERVAL = 25000;
 
 int FileIOFlag = 0;
 int TimerFlag = 0;
-extern u_int LispWindowFd;
+extern int LispWindowFd;
 
 /************************************************************************/
 /*									*/
diff --git a/src/tty.c b/src/tty.c
index 3be69b7..a0cc488 100644
--- a/src/tty.c
+++ b/src/tty.c
@@ -18,7 +18,7 @@ DLTTY_IN_CSB *DLTTYIn;
 DLTTY_OUT_CSB *DLTTYOut;
 
 char *TTY_Dev;
-int TTY_Fd;
+int TTY_Fd = -1;
 extern fd_set LispReadFds;
 struct sgttyb TTY_Mode;
 
diff --git a/src/xinit.c b/src/xinit.c
index 7ed4d18..0177882 100644
--- a/src/xinit.c
+++ b/src/xinit.c
@@ -99,9 +99,6 @@ void init_Xevent(DspInterface dsp)
   XSelectInput(dsp->display_id, dsp->SWGrav, GravMask);
   XSelectInput(dsp->display_id, dsp->NWGrav, GravMask);
 
-#if defined(OS5) && defined(I_SETSIG)
-  ioctl(ConnectionNumber(dsp->display_id), I_SETSIG, S_INPUT); /* so we see X events fast */
-#endif
 } /*end init_Xevent */
 
 /************************************************************************/