--- xxgdb-1.12-org/calldbx.c	2012-10-26 17:17:49.810750909 -0700
+++ xxgdb-1.12/calldbx.c	2012-10-26 17:53:59.209918816 -0700
@@ -69,6 +69,12 @@
  *    create_io_window(): create an io window for gdb to use 
  */
 
+#ifdef linux
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -126,6 +132,13 @@
 {
     int master;
     
+#ifdef _POSIX_SOURCE
+    if ((master = posix_openpt (O_RDWR|O_NOCTTY)) < 0) {
+	perror("posix_openpt failed:");
+    } else {
+	return master;
+    }
+#else
 #ifdef SVR4				/* (MJH) Use STREAMS */
 
     if((master = open(MASTER_CLONE, O_RDWR)) < 0)
@@ -152,6 +165,7 @@
 	}
 #endif
 #endif /* SVR4 */
+#endif /*  _POSIX_SOURCE */
 
 #ifdef GDB
     fprintf(stderr, "xxgdb: all ptys in use\n");
@@ -167,7 +181,28 @@
 {
     int slave;
 
-#ifdef SVR4				/* (MJH) */
+#ifdef _POSIX_SOURCE
+    char *slave_name = ptsname (master);
+    if (slave_name == NULL) {
+	perror ("Pseudo-tty slave");
+	exit (2);
+    } // end if
+    if (grantpt (master) < 0) {
+	perror ("grantpt error");
+	exit (3);
+    }
+    if (unlockpt (master) < 0) {
+	perror ("unlockpt error");
+	exit (4);
+    }
+    if ((slave = open (slave_name, O_RDWR)) < 0) {
+	perror (slave_name);
+	exit (5);
+    } // end if
+    return slave;
+#else
+#ifdef SVR4		
+	/* (MJH) */
     char *slave_name = "unknown";
     extern char *ptsname(int master);
     void (*handler)();
@@ -194,6 +229,7 @@
 	    }
     return slave;
 #endif /* SVR4 */
+#endif /*  _POSIX_SOURCE */
 }
 
 #ifdef CREATE_IO_WINDOW 
@@ -230,7 +266,7 @@
     {
 	/* child */
 	/* printf("xterm xterm -l -e xxgdbiowin\n");*/
-	if (execlp("xterm", "xterm", "-e", "xxgdbiowin", 0))
+	if (execlp("xterm", "xterm", "-e", "xxgdbiowin", NULL))
 	{
 	    printf("exec of 'xterm -e xxgdbiowin' fails\n");
 	    unlink("/tmp/iowindowtty");