diff -urNad xxgdb-1.12~/calldbx.c xxgdb-1.12/calldbx.c
--- xxgdb-1.12~/calldbx.c	1996-10-02 10:59:45.000000000 +0200
+++ xxgdb-1.12/calldbx.c	2008-05-16 17:44:05.000000000 +0200
@@ -85,8 +85,10 @@
 #include        <sys/un.h>
 #endif /* CREATE_IO_WINDOW */
 
-#ifdef SVR4
+#if defined(SVR4) || defined(UNIX98)
 #define MASTER_CLONE "/dev/ptmx"
+#endif
+#ifdef SVR4
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/stropts.h>
@@ -125,13 +127,14 @@
 {
     int master;
     
-#ifdef SVR4				/* (MJH) Use STREAMS */
+#if defined(SVR4) || defined(UNIX98)
 
     if((master = open(MASTER_CLONE, O_RDWR)) < 0)
 	perror(MASTER_CLONE);
     else
 	return master;
-#else
+#endif
+#if !defined(SVR4) && !defined(UNIX98)
     int  i;
     char c;
 
@@ -150,7 +153,7 @@
 #ifndef sco
 	}
 #endif
-#endif /* SVR4 */
+#endif /* !defined(SVR4) && !defined(UNIX98) */
 
 #ifdef GDB
     fprintf(stderr, "xxgdb: all ptys in use\n");
@@ -166,6 +169,25 @@
 {
     int slave;
 
+#if defined(UNIX98)
+
+    int n;
+    int zero=0;
+    char ptsname[16];
+
+    if (ioctl(master, TIOCGPTN, &n) < 0)
+	exit(2);
+    snprintf(ptsname,sizeof(ptsname),"/dev/pts/%i", n);
+    if (ioctl(master, TIOCSPTLCK, &zero) < 0)
+	exit(3);
+    if ((slave = open(ptsname, O_RDWR)) < 0) {
+	perror(ptsname);
+	exit(4);
+    }
+    return slave;
+
+#else
+    
 #ifdef SVR4				/* (MJH) */
     char *slave_name = "unknown";
     extern char *ptsname(int master);
@@ -193,6 +215,8 @@
 	    }
     return slave;
 #endif /* SVR4 */
+
+#endif /* UNIX98 */
 }
 
 #ifdef CREATE_IO_WINDOW