diff --git a/Xext/xf86bigfont.c b/Xext/xf86bigfont.c
index d5c5704de..dabbdd6e0 100644
--- a/Xext/xf86bigfont.c
+++ b/Xext/xf86bigfont.c
@@ -50,7 +50,7 @@
 #ifdef SVR4
 #include <sys/sysmacros.h>
 #endif
-#if defined(ISC) || defined(__CYGWIN__) || defined(__SCO__)
+#if defined(__CYGWIN__) || defined(__SCO__)
 #include <sys/param.h>
 #include <sys/sysmacros.h>
 #endif
diff --git a/damageext/damageext.c b/damageext/damageext.c
old mode 100755
new mode 100644
diff --git a/hw/xfree86/loader/os.c b/hw/xfree86/loader/os.c
index a73ef939e..ef9ac38b4 100644
--- a/hw/xfree86/loader/os.c
+++ b/hw/xfree86/loader/os.c
@@ -52,8 +52,6 @@
 #define OSNAME "hurd"
 #elif defined(__SCO__)
 #define OSNAME "sco"
-#elif defined(ISC)
-#define OSNAME "isc"
 #elif defined(SVR4) && defined(sun)
 #define OSNAME "solaris"
 #elif defined(SVR5)
diff --git a/hw/xfree86/os-support/xf86_OSlib.h b/hw/xfree86/os-support/xf86_OSlib.h
index a12e0e8dd..48d922301 100644
--- a/hw/xfree86/os-support/xf86_OSlib.h
+++ b/hw/xfree86/os-support/xf86_OSlib.h
@@ -98,16 +98,10 @@
 # include <termio.h>
 # include <sys/stat.h>
 # include <sys/types.h>
-# if defined(__SCO__) || defined(ISC)
+# if defined(__SCO__) 
 # include <sys/param.h>
 # endif
 
-# ifdef ISC
-#  define TIOCMSET (TIOC|26)	/* set all modem bits */
-#  define TIOCMBIS (TIOC|27)	/* bis modem bits */
-#  define TIOCMBIC (TIOC|28)	/* bic modem bits */
-#  define TIOCMGET (TIOC|29)	/* get all modem bits */
-# endif
 
 # include <errno.h>
 
@@ -203,10 +197,6 @@
 #  define POSIX_TTY
 # endif /* SVR4 */
 
-# ifdef ISC
-#  include <termios.h>
-#  define POSIX_TTY
-# endif
 
 # if defined(sun) && (defined (__i386__) || defined(__i386)) && defined (SVR4) && !defined(__SOL8__)
 #  define USE_VT_SYSREQ
@@ -446,12 +436,6 @@
 # endif /* MAXPATHLEN */
 #endif /* !PATH_MAX */
 
-#if defined(ISC)
-#define rint(x) RInt(x)
-double RInt(
-	double x
-);
-#endif
 
 #ifndef DEV_MEM
 #define DEV_MEM "/dev/mem"
diff --git a/hw/xwin/winmessages.h b/hw/xwin/winmessages.h
old mode 100755
new mode 100644
diff --git a/miext/damage/damage.c b/miext/damage/damage.c
old mode 100755
new mode 100644
diff --git a/miext/damage/damage.h b/miext/damage/damage.h
old mode 100755
new mode 100644
diff --git a/miext/damage/damagestr.h b/miext/damage/damagestr.h
old mode 100755
new mode 100644
diff --git a/os/access.c b/os/access.c
index efc9a458b..c91212b1b 100644
--- a/os/access.c
+++ b/os/access.c
@@ -80,7 +80,7 @@ SOFTWARE.
 #include <sys/ioctl.h>
 #include <ctype.h>
 
-#if defined(TCPCONN) || defined(STREAMSCONN) || defined(ISC) || defined(__SCO__)
+#if defined(TCPCONN) || defined(STREAMSCONN) || defined(__SCO__)
 #include <netinet/in.h>
 #endif /* TCPCONN || STREAMSCONN || ISC || __SCO__ */
 #ifdef DNETCONN
@@ -100,10 +100,6 @@ SOFTWARE.
 #endif
 #if defined(SYSV) &&  defined(__i386__)
 # include <sys/stream.h>
-# ifdef ISC
-#  include <sys/stropts.h>
-#  include <sys/sioctl.h>
-# endif /* ISC */
 #endif
 #ifdef __GNU__
 #undef SIOCGIFCONF
@@ -283,7 +279,7 @@ AccessUsingXdmcp (void)
 }
 
 
-#if ( defined(SVR4) && !defined(SCO325) && !defined(sun) || defined(ISC)) && defined(SIOCGIFCONF) && !defined(USE_SIOCGLIFCONF)
+#if  defined(SVR4) && !defined(SCO325) && !defined(sun)  && defined(SIOCGIFCONF) && !defined(USE_SIOCGLIFCONF)
 
 /* Deal with different SIOCGIFCONF ioctl semantics on these OSs */
 
@@ -300,17 +296,6 @@ ifioctl (int fd, int cmd, char *arg)
     {
 	ioc.ic_len = ((struct ifconf *) arg)->ifc_len;
 	ioc.ic_dp = ((struct ifconf *) arg)->ifc_buf;
-#ifdef ISC
-	/* SIOCGIFCONF is somewhat brain damaged on ISC. The argument
-	 * buffer must contain the ifconf structure as header. Ifc_req
-	 * is also not a pointer but a one element array of ifreq
-	 * structures. On return this array is extended by enough
-	 * ifreq fields to hold all interfaces. The return buffer length
-	 * is placed in the buffer header.
-	 */
-        ((struct ifconf *) ioc.ic_dp)->ifc_len =
-                                         ioc.ic_len - sizeof(struct ifconf);
-#endif
     }
     else
     {
@@ -321,14 +306,6 @@ ifioctl (int fd, int cmd, char *arg)
     if (ret >= 0 && cmd == SIOCGIFCONF)
 #ifdef SVR4
 	((struct ifconf *) arg)->ifc_len = ioc.ic_len;
-#endif
-#ifdef ISC
-    {
-	((struct ifconf *) arg)->ifc_len =
-				 ((struct ifconf *)ioc.ic_dp)->ifc_len;
-	((struct ifconf *) arg)->ifc_buf = 
-			(caddr_t)((struct ifconf *)ioc.ic_dp)->ifc_req;
-    }
 #endif
     return(ret);
 }
@@ -609,11 +586,7 @@ DefineSelf (int fd)
     ifc.ifc_buf = bufptr;
 
 #define IFC_IOCTL_REQ SIOCGIFCONF
-#ifdef ISC
-#define IFC_IFC_REQ (struct ifreq *) ifc.ifc_buf
-#else
 #define IFC_IFC_REQ ifc.ifc_req
-#endif /* ISC */
 #define IFC_IFC_LEN ifc.ifc_len
 #define IFR_IFR_ADDR ifr->ifr_addr
 #define IFR_IFR_NAME ifr->ifr_name
diff --git a/xfixes/cursor.c b/xfixes/cursor.c
old mode 100755
new mode 100644
diff --git a/xfixes/saveset.c b/xfixes/saveset.c
old mode 100755
new mode 100644
diff --git a/xfixes/select.c b/xfixes/select.c
old mode 100755
new mode 100644
diff --git a/xfixes/xfixes.c b/xfixes/xfixes.c
old mode 100755
new mode 100644
diff --git a/xfixes/xfixes.h b/xfixes/xfixes.h
old mode 100755
new mode 100644
diff --git a/xfixes/xfixesint.h b/xfixes/xfixesint.h
old mode 100755
new mode 100644