@@ -14,35 +14,41 @@
  * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
  * file.
  */
 
 #include "config.h"
+
+#include <string.h>
 
 #import "OFUnlockFailedException.h"
 #import "OFString.h"
 
 @implementation OFUnlockFailedException
-@synthesize lock = _lock;
+@synthesize lock = _lock, errNo = _errNo;
 
 + (instancetype)exceptionWithLock: (id <OFLocking>)lock
+			    errNo: (int)errNo
 {
-	return [[[self alloc] initWithLock: lock] autorelease];
-}
-
-- (instancetype)init
-{
-	return [self initWithLock: nil];
+	return [[[self alloc] initWithLock: lock
+				     errNo: errNo] autorelease];
 }
 
 - (instancetype)initWithLock: (id <OFLocking>)lock
+		       errNo: (int)errNo
 {
 	self = [super init];
 
 	_lock = [lock retain];
+	_errNo = errNo;
 
 	return self;
 }
+
+- (instancetype)init
+{
+	OF_INVALID_INIT_METHOD
+}
 
 - (void)dealloc
 {
 	[_lock release];
 
@@ -49,12 +55,10 @@
 	[super dealloc];
 }
 
 - (OFString *)description
 {
-	if (_lock != nil)
-		return [OFString stringWithFormat:
-		    @"A lock of type %@ could not be unlocked!", _lock.class];
-	else
-		return @"A lock could not be unlocked!";
+	return [OFString stringWithFormat:
+	    @"A lock of type %@ could not be unlocked: %s",
+	    _lock.class, strerror(_errNo)];
 }
 @end