Index: src/OFString+PathAdditions.h
==================================================================
--- src/OFString+PathAdditions.h
+++ src/OFString+PathAdditions.h
@@ -26,10 +26,15 @@
 #ifdef __cplusplus
 }
 #endif
 
 @interface OFString (PathAdditions)
+/*!
+ * @brief Whether the path is an absolute path.
+ */
+@property (readonly, nonatomic, getter=isAbsolutePath) bool absolutePath;
+
 /*!
  * @brief The components of the string when interpreted as a path.
  */
 @property (readonly, nonatomic) OFArray OF_GENERIC(OFString *) *pathComponents;
 

Index: src/OFString+PathAdditions_DOS.m
==================================================================
--- src/OFString+PathAdditions_DOS.m
+++ src/OFString+PathAdditions_DOS.m
@@ -27,10 +27,23 @@
 @implementation OFString (PathAdditions)
 + (OFString *)pathWithComponents: (OFArray *)components
 {
 	return [components componentsJoinedByString: @"\\"];
 }
+
+- (bool)isAbsolutePath
+{
+	void *pool = objc_autoreleasePoolPush();
+	const char *UTF8String = [self UTF8String];
+	size_t UTF8StringLength = [self UTF8StringLength];
+	bool ret = (UTF8StringLength >= 3 && UTF8String[1] == ':' &&
+	    (UTF8String[2] == '\\' || UTF8String[2] == '/'));
+
+	objc_autoreleasePoolPop(pool);
+
+	return ret;
+}
 
 - (OFArray *)pathComponents
 {
 	OFMutableArray OF_GENERIC(OFString *) *ret = [OFMutableArray array];
 	void *pool = objc_autoreleasePoolPush();

Index: src/OFString+PathAdditions_UNIX.m
==================================================================
--- src/OFString+PathAdditions_UNIX.m
+++ src/OFString+PathAdditions_UNIX.m
@@ -27,10 +27,15 @@
 @implementation OFString (PathAdditions)
 + (OFString *)pathWithComponents: (OFArray *)components
 {
 	return [components componentsJoinedByString: @"/"];
 }
+
+- (bool)isAbsolutePath
+{
+	return [self hasPrefix: @"/"];
+}
 
 - (OFArray *)pathComponents
 {
 	OFMutableArray OF_GENERIC(OFString *) *ret = [OFMutableArray array];
 	void *pool = objc_autoreleasePoolPush();

Index: tests/OFStringTests.m
==================================================================
--- tests/OFStringTests.m
+++ tests/OFStringTests.m
@@ -550,10 +550,20 @@
 
 	TEST(@"-[stringByPrependingString:]",
 	    [[C(@"foo") stringByPrependingString: @"bar"] isEqual: @"barfoo"])
 
 #ifdef OF_HAVE_FILES
+# if defined(OF_WINDOWS) || defined(OF_MSDOS)
+	TEST(@"-[isAbsolutePath]",
+	    [C(@"C:\\foo") isAbsolutePath] && [C(@"a:/foo") isAbsolutePath] &&
+	    ![C(@"foo") isAbsolutePath] && ![C(@"b:foo") isAbsolutePath])
+# else
+	TEST(@"-[isAbsolutePath]",
+	    [C(@"/foo") isAbsolutePath] && [C(@"/foo/bar") isAbsolutePath] &&
+	    ![C(@"foo/bar") isAbsolutePath] && ![C(@"foo") isAbsolutePath])
+# endif
+
 	s[0] = [mutableStringClass stringWithString: @"foo"];
 # if defined(OF_WINDOWS) || defined(OF_MSDOS)
 	[s[0] appendString: @"\\"];
 # else
 	[s[0] appendString: @"/"];