diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 547f0b139..6fa859452 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,11 @@
+2010-08-19  Corinna Vinschen  <corinna@vinschen.de>
+
+	* external.cc (sync_wincwd): New function.
+	(cygwin_internal): Rename CW_SETCWD to CW_SYNC_WINCWD.  Call
+	sync_wincwd from here.
+	* include/sys/cygwin.h (cygwin_getinfo_types): Rename CW_SETCWD to
+	CW_SYNC_WINCWD.
+
 2010-08-18  Christopher Faylor  <me+cygwin@cgf.cx>
 
 	* external.cc (CW_SETCWD): New option.
diff --git a/winsup/cygwin/external.cc b/winsup/cygwin/external.cc
index 53ce5b1b8..e8d3580f4 100644
--- a/winsup/cygwin/external.cc
+++ b/winsup/cygwin/external.cc
@@ -162,6 +162,29 @@ sync_winenv ()
   free (envblock);
 }
 
+/* Synchronize Win32 CWD with Cygwin CWD.  Return -1 and set errno if
+   setting the Win32 CWD fails. */
+static unsigned long
+sync_wincwd ()
+{
+  unsigned long ret = (unsigned long) -1;
+  /* Lock cwd.  We're accessing it directly here. */
+  cygheap->cwd.cwd_lock.acquire ();
+  /* First check if the path can work at all.  Fortunately we already have
+     an error code in the cwd, which was stored there for the sake of
+     spawn_guts. */
+  if (cygheap->cwd.get_error ())
+    set_errno (cygheap->cwd.get_error ());
+  /* Of course, SetCurrentDirectoryW still can fail, for instance, if the
+     CWD has been removed or renamed in the meantime. */
+  else if (!SetCurrentDirectoryW (cygheap->cwd.win32.Buffer))
+    __seterrno ();
+  else
+    ret = 0;
+  cygheap->cwd.cwd_lock.release ();
+  return ret;
+}
+
 /*
  * Cygwin-specific wrapper for win32 ExitProcess and TerminateProcess.
  * It ensures that the correct exit code, derived from the specified
@@ -514,13 +537,10 @@ cygwin_internal (cygwin_getinfo_types t, ...)
 	  res = (uintptr_t) strerror (err);
 	}
 	break;
+      case CW_SYNC_WINCWD:
+	res = sync_wincwd ();
+	break;
 
-      case CW_SETCWD:
-	{
-	  cygheap->cwd.cwd_lock.acquire ();
-	  PWCHAR cwd = cygheap->cwd.win32.Buffer;
-	  res = !SetCurrentDirectoryW (cwd);
-	}
       default:
 	set_errno (ENOSYS);
     }
diff --git a/winsup/cygwin/include/sys/cygwin.h b/winsup/cygwin/include/sys/cygwin.h
index 158fa0db1..aa4ce4d7c 100644
--- a/winsup/cygwin/include/sys/cygwin.h
+++ b/winsup/cygwin/include/sys/cygwin.h
@@ -150,7 +150,7 @@ typedef enum
     CW_CVT_MNT_OPTS,
     CW_LST_MNT_OPTS,
     CW_STRERROR,
-    CW_SETCWD
+    CW_SYNC_WINCWD
   } cygwin_getinfo_types;
 
 /* Token type for CW_SET_EXTERNAL_TOKEN */