diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 4b697be2c..2d9a77c7c 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,24 @@
+2010-07-05  Corinna Vinschen  <corinna@vinschen.de>
+
+	Align seekdir and telldir API to POSIX definition.
+	* Makefile.in (NEW_FUNCTIONS): Remove seekdir and telldir mappings.
+	* dir.cc (telldir): Move functionality from telldir64 here.  Use
+	long, rather than _off_t.
+	(telldir64): Just call telldir.  Only keep for backward compatibility.
+	(seekdir): Move functionality from seekdir64 here.  Use long, rather
+	than _off_t.
+	(seekdir64): Just call seekdir.  Only keep for backward compatibility.
+	* fhandler.h: Throughout, change prototypes of seekdir and telldir
+	methods to use long, rather than _off64_t.
+	* fhandler_disk_file.cc: Change aforementioned methods accordingly.
+	* fhandler_netdrive.cc: Ditto.
+	* fhandler_registry.cc: Ditto.
+	* fhandler_virtual.cc: Ditto.
+	* include/sys/dirent.h (struct __DIR): Change __d_position from
+	_off_t to long to reflect API change.
+	(telldir): Change prototype to use long, rather than off_t.
+	(seekdir): Ditto.
+
 2010-07-04  Christopher Faylor  <me+cygwin@cgf.cx>
 
 	* path.cc (path_conv::check): Move fs-specific settings to a point
diff --git a/winsup/cygwin/Makefile.in b/winsup/cygwin/Makefile.in
index 3f4c0044f..e4e5be66a 100644
--- a/winsup/cygwin/Makefile.in
+++ b/winsup/cygwin/Makefile.in
@@ -210,7 +210,6 @@ NEW_FUNCTIONS:=$(addprefix --replace=,\
 	mknod=_mknod32 \
 	mmap=_mmap64 \
 	open=_open64 \
-	seekdir=_seekdir64 \
 	setegid=_setegid32 \
 	seteuid=_seteuid32 \
 	setgid=_setgid32 \
@@ -219,7 +218,6 @@ NEW_FUNCTIONS:=$(addprefix --replace=,\
 	setreuid=_setreuid32 \
 	setuid=_setuid32 \
 	stat=_stat64 \
-	telldir=_telldir64 \
 	timezone= \
 	tmpfile=_tmpfile64 \
 	truncate=_truncate64 \
diff --git a/winsup/cygwin/dir.cc b/winsup/cygwin/dir.cc
index 641aabe4b..c51cff701 100644
--- a/winsup/cygwin/dir.cc
+++ b/winsup/cygwin/dir.cc
@@ -187,8 +187,9 @@ readdir_r (DIR *dir, dirent *de, dirent **ode)
   return res;
 }
 
-extern "C" _off64_t
-telldir64 (DIR *dir)
+/* telldir */
+extern "C" long
+telldir (DIR *dir)
 {
   myfault efault;
   if (efault.faulted (EFAULT))
@@ -199,15 +200,18 @@ telldir64 (DIR *dir)
   return ((fhandler_base *) dir->__fh)->telldir (dir);
 }
 
-/* telldir */
-extern "C" _off_t
-telldir (DIR *dir)
+/* telldir was never defined using off_t in POSIX, only in early versions
+   of glibc.  We have to keep the function in as entry point for backward
+   compatibility. */
+extern "C" _off64_t
+telldir64 (DIR *dir)
 {
-  return telldir64 (dir);
+  return (_off64_t) telldir (dir);
 }
 
+/* seekdir */
 extern "C" void
-seekdir64 (DIR *dir, _off64_t loc)
+seekdir (DIR *dir, long loc)
 {
   myfault efault;
   if (efault.faulted (EFAULT))
@@ -219,11 +223,13 @@ seekdir64 (DIR *dir, _off64_t loc)
   return ((fhandler_base *) dir->__fh)->seekdir (dir, loc);
 }
 
-/* seekdir */
+/* seekdir was never defined using off_t in POSIX, only in early versions
+   of glibc.  We have to keep the function in as entry point for backward
+   compatibility. */
 extern "C" void
-seekdir (DIR *dir, _off_t loc)
+seekdir64 (DIR *dir, _off64_t loc)
 {
-  seekdir64 (dir, (_off64_t)loc);
+  seekdir (dir, (long) loc);
 }
 
 /* rewinddir: POSIX 5.1.2.1 */
diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc
index bd4422a89..a8264e403 100644
--- a/winsup/cygwin/fhandler.cc
+++ b/winsup/cygwin/fhandler.cc
@@ -1441,7 +1441,7 @@ fhandler_base::readdir (DIR *, dirent *)
   return ENOTDIR;
 }
 
-_off64_t
+long
 fhandler_base::telldir (DIR *)
 {
   set_errno (ENOTDIR);
@@ -1449,7 +1449,7 @@ fhandler_base::telldir (DIR *)
 }
 
 void
-fhandler_base::seekdir (DIR *, _off64_t)
+fhandler_base::seekdir (DIR *, long)
 {
   set_errno (ENOTDIR);
 }
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index 561ada18b..54e9d0694 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -378,8 +378,8 @@ class fhandler_base
   virtual int rmdir ();
   virtual DIR *opendir (int fd) __attribute__ ((regparm (2)));
   virtual int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
-  virtual _off64_t telldir (DIR *);
-  virtual void seekdir (DIR *, _off64_t);
+  virtual long telldir (DIR *);
+  virtual void seekdir (DIR *, long);
   virtual void rewinddir (DIR *);
   virtual int closedir (DIR *);
   virtual bool is_slow () {return false;}
@@ -774,8 +774,8 @@ class fhandler_disk_file: public fhandler_base
   int rmdir ();
   DIR *opendir (int fd) __attribute__ ((regparm (2)));
   int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
-  _off64_t telldir (DIR *);
-  void seekdir (DIR *, _off64_t);
+  long telldir (DIR *);
+  void seekdir (DIR *, long);
   void rewinddir (DIR *);
   int closedir (DIR *);
 
@@ -1333,8 +1333,8 @@ class fhandler_virtual : public fhandler_base
 
   virtual int exists();
   DIR *opendir (int fd) __attribute__ ((regparm (2)));
-  _off64_t telldir (DIR *);
-  void seekdir (DIR *, _off64_t);
+  long telldir (DIR *);
+  void seekdir (DIR *, long);
   void rewinddir (DIR *);
   int closedir (DIR *);
   ssize_t __stdcall write (const void *ptr, size_t len);
@@ -1372,7 +1372,7 @@ class fhandler_netdrive: public fhandler_virtual
   fhandler_netdrive ();
   int exists();
   int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
-  void seekdir (DIR *, _off64_t);
+  void seekdir (DIR *, long);
   void rewinddir (DIR *);
   int closedir (DIR *);
   int open (int flags, mode_t mode = 0);
@@ -1390,8 +1390,8 @@ class fhandler_registry: public fhandler_proc
   void set_name (path_conv &pc);
   int exists();
   int readdir (DIR *, dirent *) __attribute__ ((regparm (3)));
-  _off64_t telldir (DIR *);
-  void seekdir (DIR *, _off64_t);
+  long telldir (DIR *);
+  void seekdir (DIR *, long);
   void rewinddir (DIR *);
   int closedir (DIR *);
 
diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc
index 00d4d4a4e..a284b81f9 100644
--- a/winsup/cygwin/fhandler_disk_file.cc
+++ b/winsup/cygwin/fhandler_disk_file.cc
@@ -2128,14 +2128,14 @@ go_ahead:
   return res;
 }
 
-_off64_t
+long
 fhandler_disk_file::telldir (DIR *dir)
 {
   return dir->__d_position;
 }
 
 void
-fhandler_disk_file::seekdir (DIR *dir, _off64_t loc)
+fhandler_disk_file::seekdir (DIR *dir, long loc)
 {
   rewinddir (dir);
   while (loc > dir->__d_position)
diff --git a/winsup/cygwin/fhandler_netdrive.cc b/winsup/cygwin/fhandler_netdrive.cc
index 4cce69753..f3339a653 100644
--- a/winsup/cygwin/fhandler_netdrive.cc
+++ b/winsup/cygwin/fhandler_netdrive.cc
@@ -259,7 +259,7 @@ out:
 }
 
 void
-fhandler_netdrive::seekdir (DIR *dir, _off64_t pos)
+fhandler_netdrive::seekdir (DIR *dir, long pos)
 {
   rewinddir (dir);
   if (pos < 0)
diff --git a/winsup/cygwin/fhandler_registry.cc b/winsup/cygwin/fhandler_registry.cc
index 9c68b2cdd..e414efbb3 100644
--- a/winsup/cygwin/fhandler_registry.cc
+++ b/winsup/cygwin/fhandler_registry.cc
@@ -643,14 +643,14 @@ out:
   return res;
 }
 
-_off64_t
+long
 fhandler_registry::telldir (DIR * dir)
 {
   return dir->__d_position & REG_POSITION_MASK;
 }
 
 void
-fhandler_registry::seekdir (DIR * dir, _off64_t loc)
+fhandler_registry::seekdir (DIR * dir, long loc)
 {
   /* Unfortunately cannot simply set __d_position due to transition from sub-keys to
    * values.
diff --git a/winsup/cygwin/fhandler_virtual.cc b/winsup/cygwin/fhandler_virtual.cc
index c47d2ccdd..3becf03e9 100644
--- a/winsup/cygwin/fhandler_virtual.cc
+++ b/winsup/cygwin/fhandler_virtual.cc
@@ -97,13 +97,14 @@ fhandler_virtual::opendir (int fd)
   return res;
 }
 
-_off64_t fhandler_virtual::telldir (DIR * dir)
+long
+fhandler_virtual::telldir (DIR * dir)
 {
   return dir->__d_position;
 }
 
 void
-fhandler_virtual::seekdir (DIR * dir, _off64_t loc)
+fhandler_virtual::seekdir (DIR * dir, long loc)
 {
   dir->__flags |= dirent_saw_dot | dirent_saw_dot_dot;
   dir->__d_position = loc;
diff --git a/winsup/cygwin/include/sys/dirent.h b/winsup/cygwin/include/sys/dirent.h
index fa059ec30..3d441a20c 100644
--- a/winsup/cygwin/include/sys/dirent.h
+++ b/winsup/cygwin/include/sys/dirent.h
@@ -38,7 +38,7 @@ typedef struct __DIR
   unsigned long __d_cookie;
   struct dirent *__d_dirent;
   char *__d_dirname;			/* directory name with trailing '*' */
-  _off_t __d_position;			/* used by telldir/seekdir */
+  long __d_position;			/* used by telldir/seekdir */
   int __d_fd;
   unsigned __d_internal;
   void *__handle;
@@ -58,8 +58,8 @@ int dirfd (DIR *);
 
 #ifndef _POSIX_SOURCE
 #ifndef __INSIDE_CYGWIN__
-off_t telldir (DIR *);
-void seekdir (DIR *, off_t loc);
+long telldir (DIR *);
+void seekdir (DIR *, long loc);
 #endif
 
 int scandir (const char *__dir,