diff --git a/core-foundation-sys/src/url.rs b/core-foundation-sys/src/url.rs
index 3081ec2..79fdc05 100644
--- a/core-foundation-sys/src/url.rs
+++ b/core-foundation-sys/src/url.rs
@@ -124,7 +124,8 @@ extern {
     //fn CFURLCreateStringByAddingPercentEscapes
     //fn CFURLCreateStringByReplacingPercentEscapes
     //fn CFURLCreateStringByReplacingPercentEscapesUsingEncoding
-    //fn CFURLGetFileSystemRepresentation
+    pub fn CFURLGetFileSystemRepresentation(anURL: CFURLRef, resolveAgainstBase: Boolean, buffer: *mut u8, maxBufLen: CFIndex) -> Boolean;
+
     //fn CFURLGetFSRef
     pub fn CFURLGetString(anURL: CFURLRef) -> CFStringRef;