@@ -16,17 +16,17 @@
 
 #define __NO_EXT_QNX
 
 #include "config.h"
 
+#include <assert.h>
+#include <errno.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
-#include <assert.h>
-
 #include <fcntl.h>
 
 #ifndef _WIN32
 # include <signal.h>
 #endif
@@ -1484,21 +1484,23 @@
 
 		readImplemented = true;
 
 		if (readFlags == -1)
 			@throw [OFSetOptionFailedException
-			    exceptionWithStream: self];
+			    exceptionWithStream: self
+					  errNo: errno];
 
 		if (enable)
 			readFlags &= ~O_NONBLOCK;
 		else
 			readFlags |= O_NONBLOCK;
 
 		if (fcntl([self fileDescriptorForReading], F_SETFL,
 		    readFlags) == -1)
 			@throw [OFSetOptionFailedException
-			    exceptionWithStream: self];
+			    exceptionWithStream: self
+					  errNo: errno];
 	} @catch (OFNotImplementedException *e) {
 	}
 
 	@try {
 		int writeFlags;
@@ -1507,21 +1509,23 @@
 
 		writeImplemented = true;
 
 		if (writeFlags == -1)
 			@throw [OFSetOptionFailedException
-			    exceptionWithStream: self];
+			    exceptionWithStream: self
+					  errNo: errno];
 
 		if (enable)
 			writeFlags &= ~O_NONBLOCK;
 		else
 			writeFlags |= O_NONBLOCK;
 
 		if (fcntl([self fileDescriptorForWriting], F_SETFL,
 		    writeFlags) == -1)
 			@throw [OFSetOptionFailedException
-			    exceptionWithStream: self];
+			    exceptionWithStream: self
+					  errNo: errno];
 	} @catch (OFNotImplementedException *e) {
 	}
 
 	if (!readImplemented && !writeImplemented)
 		@throw [OFNotImplementedException exceptionWithSelector: _cmd