diff -r fb70ea8b7b2d Doc/library/os.rst
--- a/Doc/library/os.rst	Tue Apr 26 09:31:11 2016 +0300
+++ b/Doc/library/os.rst	Wed May 04 11:09:57 2016 +0200
@@ -671,6 +671,27 @@
               pass
 
 
+.. function:: copy_file_range(in, out, count, offset_in=None, offset_out=None, flags=0)
+
+   Copy *count* bytes from file descriptor *in*, starting from offset
+   *offset_in*, to file descriptor *out*, starting from offset *offset_out*.
+   If *offset_in* is None, then *in* is read from the current position;
+   respectively for *offset_out*. The files pointed by *in* and *out*
+   must reside in the same filesystem, otherwise a :exc:`OSError` is
+   raised with :attr:`~OSError.errno` set to :data:`errno.EXDEV`.
+
+   This copy is done without using any user space buffers, and some
+   filesystems could implement optimizations. The copy is done as if
+   both files are opened as binay, so no transcoding is possible.
+
+   The flags argument is provided to allow for future extensions and
+   currently must be set to 0.
+
+   Availability: some recent flavors of Unix (see the man page
+   :manpage:`copy_file_range(2)` for further information).
+
+   .. versionadded:: 3.6
+
 .. function:: device_encoding(fd)
 
    Return a string describing the encoding of the device associated with *fd*
diff -r fb70ea8b7b2d Modules/posixmodule.c
--- a/Modules/posixmodule.c	Tue Apr 26 09:31:11 2016 +0300
+++ b/Modules/posixmodule.c	Wed May 04 11:09:57 2016 +0200
@@ -87,6 +87,11 @@
 #include <sys/sendfile.h>
 #endif
 
+#ifdef HAVE_COPY_FILE_RANGE
+#include <sys/syscall.h>
+#include <unistd.h>
+#endif
+
 #ifdef HAVE_SCHED_H
 #include <sched.h>
 #endif
@@ -8394,6 +8399,75 @@
 }
 #endif /* HAVE_SENDFILE */
 
+#ifdef HAVE_COPY_FILE_RANGE
+/* modified example found in copy_file_range()'s man page: */
+/* ssize_t so it can return -1 */
+static ssize_t
+copy_file_range(int fd_in, loff_t *off_in, int fd_out, loff_t *off_out,
+                size_t len, unsigned int flags)
+{
+    return syscall(__NR_copy_file_range, fd_in, off_in, fd_out, off_out,
+                   len, flags);
+}
+
+PyDoc_STRVAR(posix_copy_file_range__doc__,
+"copy_file_range(in, offset_in, out, offset_out, count, flags=0) -> \
+bytes_written\n\
+Copy count bytes from file descriptor in, starting from offset offset_in, \
+to file descriptor out, starting from offset offset_out. \
+If offset_in is None, then in is read from the current position; \
+respectively for offset_out.");
+
+static PyObject *
+posix_copy_file_range(PyObject *self, PyObject *args, PyObject *kwdict)
+{
+    int in, out;
+    off_t offset_in, *p_offset_in, offset_out, *p_offset_out;
+    Py_ssize_t count, ret;
+    int async_err = 0;
+    int flags = 0;
+    PyObject *offset_in_obj, *offset_out_obj;
+    static char *keywords[] = {"in", "out", "count",
+                               "offset_in", "offset_out", "flags", NULL};
+
+    /* O types are used to handle offset_*_obj==None -> from current position */
+    if (!PyArg_ParseTupleAndKeywords(args, kwdict, "iin|OOi:copy_file_range",
+        keywords, &in, &out, &count, &offset_in_obj, &offset_out_obj, &flags))
+            return NULL;
+
+    /* offset handling is complex. we convert the argument to a Python object.
+     * if None, then the corresponding pointer is NULL.
+     * otherwise, try to convert; if successful, use that
+     * and point the pointer there.
+     */
+    if (offset_in_obj == Py_None)
+        p_offset_in = NULL;
+    else {
+        if (!Py_off_t_converter(offset_in_obj, &offset_in))
+            return NULL;
+        p_offset_in = &offset_in;
+    }
+    if (offset_out_obj == Py_None)
+        p_offset_out = NULL;
+    else {
+        if (!Py_off_t_converter(offset_out_obj, &offset_out))
+            return NULL;
+        p_offset_out = &offset_out;
+    }
+
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        ret = copy_file_range(in, p_offset_in, out, p_offset_out, count, flags);
+        Py_END_ALLOW_THREADS
+    } while (ret < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
+
+    if (ret < 0)
+        return async_err ? NULL : posix_error();
+
+    /* we currently ignore the changes to the offsets */
+    return Py_BuildValue("n", ret);
+}
+#endif /* HAVE_COPY_FILE_RANGE */
 
 /*[clinic input]
 os.fstat
@@ -12407,6 +12481,10 @@
     {"sendfile",        (PyCFunction)posix_sendfile, METH_VARARGS | METH_KEYWORDS,
                             posix_sendfile__doc__},
 #endif
+#ifdef HAVE_COPY_FILE_RANGE
+    {"copy_file_range", (PyCFunction)posix_copy_file_range, METH_VARARGS | METH_KEYWORDS,
+                            posix_copy_file_range__doc__},
+#endif
     OS_FSTAT_METHODDEF
     OS_ISATTY_METHODDEF
     OS_PIPE_METHODDEF
@@ -11191,6 +11204,16 @@
 fi
 
 
+ac_fn_c_check_decl "$LINENO" "__NR_copy_file_range" "ac_cv_have_decl___NR_copy_file_range" "#include <sys/syscall.h>
+     #include <unistd.h>
+"
+if test "x$ac_cv_have_decl___NR_copy_file_range" = xyes; then :
+
+$as_echo "#define HAVE_COPY_FILE_RANGE 1" >>confdefs.h
+
+fi
+
+
 # For some functions, having a definition is not sufficient, since
 # we want to take their address.
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for chroot" >&5