diff --git a/library/amiga_rexxvars.c b/library/amiga_rexxvars.c
index a24b62d..f033cef 100644
--- a/library/amiga_rexxvars.c
+++ b/library/amiga_rexxvars.c
@@ -1,5 +1,5 @@
 /*
- * $Id: amiga_rexxvars.c,v 1.9 2006-09-25 15:12:47 obarthel Exp $
+ * $Id: amiga_rexxvars.c,v 1.10 2006-09-25 18:19:44 obarthel Exp $
  *
  * :ts=4
  *
@@ -142,7 +142,7 @@ CheckRexxMsg(struct RexxMsg *message)
 	if(message->rm_TaskBlock == NULL)
 		goto out;
 
-	if(NOT IsRexxMsg(message))
+	if(NOT IsRexxMsg((struct Message *)message))
 		goto out;
 
 	result = TRUE;
@@ -165,7 +165,7 @@ GetRexxVar(struct RexxMsg *message,STRPTR variable_name,STRPTR *buffer_pointer)
 
 	/* The following uses a function which was added to rexxsyslib.library V45.
 	   We therefore have a minimum library version requirement. */
-	if(RexxSysBase == NULL || RexxSysBase->lib_Version < 45 || NOT IsRexxMsg(message))
+	if(RexxSysBase == NULL || RexxSysBase->lib_Version < 45 || NOT IsRexxMsg((struct Message *)message))
 	{
 		result = ERR10_010; /* invalid message packet */
 		goto out;
@@ -195,7 +195,7 @@ SetRexxVar(struct RexxMsg *message,STRPTR variable_name,STRPTR value,ULONG lengt
 
 	/* The following uses a function which was added to rexxsyslib.library V45.
 	   We therefore have a minimum library version requirement. */
-	if(RexxSysBase == NULL || RexxSysBase->lib_Version < 45 || NOT IsRexxMsg(message))
+	if(RexxSysBase == NULL || RexxSysBase->lib_Version < 45 || NOT IsRexxMsg((struct Message *)message))
 	{
 		result = ERR10_010; /* invalid message packet */
 		goto out;
diff --git a/library/changes b/library/changes
index c819d34..872e6ea 100644
--- a/library/changes
+++ b/library/changes
@@ -1,3 +1,8 @@
+- basename() and dirname() can no longer return NULL. They truncate the
+  resulting path name instead. This is done so because some code that
+  calls basename() or dirname() does not check if the function's return
+  value is NULL.
+
 - The SetOwner() fall-back code for Kickstart 2.04 was passing the wrong
   parameters to the file system. The first (dp_Arg1) should have been
   zero. Ouch.
diff --git a/library/libgen_basename.c b/library/libgen_basename.c
index 438f22b..023c2dc 100644
--- a/library/libgen_basename.c
+++ b/library/libgen_basename.c
@@ -1,5 +1,5 @@
 /*
- * $Id: libgen_basename.c,v 1.6 2006-09-25 13:29:47 obarthel Exp $
+ * $Id: libgen_basename.c,v 1.7 2006-09-25 18:19:44 obarthel Exp $
  *
  * :ts=4
  *
@@ -34,13 +34,6 @@
 #include <string.h>
 #include <libgen.h>
 #include <stdio.h>
-#include <errno.h>
-
-/****************************************************************************/
-
-#ifndef _STDLIB_PROTOS_H
-#include "stdlib_protos.h"
-#endif /* _STDLIB_PROTOS_H */
 
 /****************************************************************************/
 
@@ -56,8 +49,8 @@ char *
 basename(const char *path)
 {
 	static char new_path[MAXPATHLEN];
-	char * result = NULL;
 	const char * str;
+	char * result;
 	size_t len;
 
 	ENTER();
@@ -89,7 +82,7 @@ basename(const char *path)
 			{
 				if(path[i] == '/')
 				{
-					len -= i;
+					len -= i+1;
 
 					str = &path[i+1];
 					break;
@@ -99,28 +92,22 @@ basename(const char *path)
 					break;
 			}
 		}
-		else
+
+		if(len == 0)
 		{
 			str = "/";
 			len = 1;
 		}
 	}
 
-	if(len + 1 > sizeof(MAXPATHLEN))
-	{
-		__set_errno(ENAMETOOLONG);
-		goto out;
-	}
+	if(len >= sizeof(new_path))
+		len = sizeof(new_path)-1;
 
 	memcpy(new_path,str,len);
 	new_path[len] = '\0';
 
 	result = new_path;
 
-	SHOWSTRING(result);
-
- out:
-
 	RETURN(result);
 	return(result);
 }
diff --git a/library/libgen_dirname.c b/library/libgen_dirname.c
index 7f74723..4578ece 100644
--- a/library/libgen_dirname.c
+++ b/library/libgen_dirname.c
@@ -1,5 +1,5 @@
 /*
- * $Id: libgen_dirname.c,v 1.6 2006-09-25 13:29:47 obarthel Exp $
+ * $Id: libgen_dirname.c,v 1.7 2006-09-25 18:19:44 obarthel Exp $
  *
  * :ts=4
  *
@@ -34,13 +34,6 @@
 #include <string.h>
 #include <libgen.h>
 #include <stdio.h>
-#include <errno.h>
-
-/****************************************************************************/
-
-#ifndef _STDLIB_PROTOS_H
-#include "stdlib_protos.h"
-#endif /* _STDLIB_PROTOS_H */
 
 /****************************************************************************/
 
@@ -56,8 +49,8 @@ char *
 dirname(const char *path)
 {
 	static char new_path[MAXPATHLEN];
-	char * result = NULL;
 	const char * str;
+	char * result;
 	size_t len;
 
 	ENTER();
@@ -67,23 +60,19 @@ dirname(const char *path)
 	else
 		SHOWSTRING(path);
 
-	if(path == NULL || path[0] == '\0')
-	{
-		str = ".";
-		len = 1;
-	}
-	else
-	{
-		size_t i;
+	str = ".";
+	len = 1;
 
+	if(path != NULL && path[0] != '\0')
+	{
 		len = strlen(path);
 
-		while(len > 0 && path[len-1] == '/')
+		while(len > 1 && path[len-1] == '/')
 			len--;
 
 		if(len > 0)
 		{
-			str = ".";
+			size_t i;
 
 			for(i = len-1 ;  ; i--)
 			{
@@ -92,6 +81,9 @@ dirname(const char *path)
 					str = path;
 					len = i;
 
+					if(i == 0)
+						len++;
+
 					break;
 				}
 
@@ -99,28 +91,16 @@ dirname(const char *path)
 					break;
 			}
 		}
-		else
-		{
-			str = "/";
-			len = 1;
-		}
 	}
 
-	if(len + 1 > sizeof(MAXPATHLEN))
-	{
-		__set_errno(ENAMETOOLONG);
-		goto out;
-	}
+	if(len >= sizeof(new_path))
+		len = sizeof(new_path)-1;
 
 	memcpy(new_path,str,len);
 	new_path[len] = '\0';
 
 	result = new_path;
 
-	SHOWSTRING(result);
-
- out:
-
 	RETURN(result);
 	return(result);
 }