diff --git a/src/nbdebug.c b/src/nbdebug.c
new file mode 100644
index 0000000..daf87a8
--- /dev/null
+++ b/src/nbdebug.c
@@ -0,0 +1,182 @@
+/* vi:set ts=8 sts=8 sw=8:
+ *
+ * VIM - Vi IMproved	by Bram Moolenaar
+ *			Visual Workshop integration by Gordon Prieur
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+
+/*
+ * NetBeans Debugging Tools. What are these tools and why are they important?
+ * There are two main tools here. The first tool is a tool for delaying or
+ * stopping gvim during startup.  The second tool is a protocol log tool.
+ *
+ * The startup delay tool is called nbdebug_wait(). This is very important for
+ * debugging startup problems because gvim will be started automatically from
+ * netbeans and cannot be run directly from a debugger. The only way to debug
+ * a gvim started by netbeans is by attaching a debugger to it. Without this
+ * tool all starup code will have completed before you can get the pid and
+ * attach.
+ *
+ * The second tool is a log tool.
+ *
+ * This code must have NBDEBUG defined for it to be compiled into vim/gvim.
+ */
+
+#ifdef NBDEBUG
+
+#include <stdarg.h>
+
+#include "vim.h"
+
+FILE		*nb_debug = NULL;
+u_int		 nb_dlevel = 0;		/* nb_debug verbosity level */
+
+void		 nbdb(char *, ...);
+void		 nbtrace(char *, ...);
+
+static int	 lookup(char *);
+#ifndef FEAT_GUI_W32
+static int	 errorHandler(Display *, XErrorEvent *);
+#endif
+
+/*
+ * nbdebug_wait	-   This function can be used to delay or stop execution of vim.
+ *		    Its normally used to delay startup while attaching a
+ *		    debugger to a running process. Since workshop starts gvim
+ *		    from a background process this is the only way to debug
+ *		    startup problems.
+ */
+
+void nbdebug_wait(
+	u_int		 wait_flags,	/* tells what to do */
+	char		*wait_var,	/* wait environment variable */
+	u_int		 wait_secs)	/* how many seconds to wait */
+{
+
+	init_homedir();			/* not inited yet */
+#ifdef USE_WDDUMP
+	WDDump(0, 0, 0);
+#endif
+
+	/* for debugging purposes only */
+	if (wait_flags & WT_ENV && wait_var && getenv(wait_var) != NULL) {
+		sleep(atoi(getenv(wait_var)));
+	} else if (wait_flags & WT_WAIT && lookup("~/.gvimwait")) {
+		sleep(wait_secs > 0 && wait_secs < 120 ? wait_secs : 20);
+	} else if (wait_flags & WT_STOP && lookup("~/.gvimstop")) {
+		int w = 1;
+		while (w) {
+			;
+		}
+	}
+}    /* end nbdebug_wait */
+
+
+void
+nbdebug_log_init(
+	char		*log_var,	/* env var with log file */
+	char		*level_var)	/* env var with nb_debug level */
+{
+	char		*file;		/* possible nb_debug output file */
+	char		*cp;		/* nb_dlevel pointer */
+
+	if (log_var && (file = getenv(log_var)) != NULL) {
+		time_t now;
+
+		nb_debug = fopen(file, "a");
+		time(&now);
+		fprintf(nb_debug, "%s", asctime(localtime(&now)));
+		if (level_var && (cp = getenv(level_var)) != NULL) {
+			nb_dlevel = strtoul(cp, NULL, 0);
+		} else {
+			nb_dlevel = NB_TRACE;	/* default level */
+		}
+		/* XSetErrorHandler(errorHandler); */
+	}
+
+}    /* end nbdebug_log_init */
+
+
+
+
+void
+nbtrace(
+	char		*fmt,
+	...)
+{
+	va_list		 ap;
+
+	if (nb_debug!= NULL && (nb_dlevel & (NB_TRACE | NB_TRACE_VERBOSE))) {
+		va_start(ap, fmt);
+		vfprintf(nb_debug, fmt, ap);
+		va_end(ap);
+		fflush(nb_debug);
+	}
+
+}    /* end nbtrace */
+
+
+void
+nbdbg(
+	char		*fmt,
+	...)
+{
+	va_list		 ap;
+
+	if (nb_debug != NULL) {
+		va_start(ap, fmt);
+		vfprintf(nb_debug, fmt, ap);
+		va_end(ap);
+		fflush(nb_debug);
+	}
+
+}    /* end nbdbg */
+
+
+static int
+lookup(
+	char		*file)
+{
+	char		 buf[BUFSIZ];
+
+	expand_env((char_u *) file, (char_u *) buf, BUFSIZ);
+	return
+#ifndef FEAT_GUI_W32
+		(access(buf, F_OK) == 0);
+#else
+		(access(buf, 0) == 0);
+#endif
+
+}    /* end lookup */
+
+#ifndef FEAT_GUI_W32
+static int
+errorHandler(
+	Display		*dpy,
+	XErrorEvent	*err)
+{
+	char		 msg[256];
+	char		 buf[256];
+
+	XGetErrorText(dpy, err->error_code, msg, sizeof(msg));
+	nbdbg("\n\nNBDEBUG Vim: X Error of failed request: %s\n", msg);
+
+	sprintf(buf, "%d", err->request_code);
+	XGetErrorDatabaseText(dpy,
+	    "XRequest", buf, "Unknown", msg, sizeof(msg));
+	nbdbg("\tMajor opcode of failed request: %d (%s)\n",
+	    err->request_code, msg);
+	if (err->request_code > 128) {
+		nbdbg("\tMinor opcode of failed request: %d\n",
+		    err->minor_code);
+	}
+
+	return 0;
+}
+#endif
+
+
+#endif /* NBDEBUG */