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	Thu May 12 15:53:41 2016 +0200
@@ -671,6 +671,28 @@
               pass
 
 
+.. function:: copy_file_range(src, dst, count, offset_src=None, offset_dst=None, flags=0)
+
+   Copy *count* bytes from file descriptor *src*, starting from offset
+   *offset_src*, to file descriptor *dst*, starting from offset *offset_dst*.
+   If *offset_src* is None, then *src* is read from the current position;
+   respectively for *offset_dst*. The files pointed by *src* and *dst*
+   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 binary, so no transcoding is possible.
+
+   The *flags* argument is provided for compatibility with the only currently
+   supported implementation (Linux >=4.5) to allow for future extensions, and
+   currently can only be 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	Thu May 12 15:53:41 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(src, dst, count, offset_src=None, offset_dst=None, flags=0) -> \
+bytes_written\n\
+Copy count bytes from file descriptor src, starting from offset offset_src, \
+to file descriptor dst, starting from offset offset_dst. \
+If offset_src is None, then src is read from the current position; \
+respectively for offset_dst.");
+
+static PyObject *
+posix_copy_file_range(PyObject *self, PyObject *args, PyObject *kwdict)
+{
+    int src, dst;
+    off_t offset_src, *p_offset_src, offset_dst, *p_offset_dst;
+    Py_ssize_t count, ret;
+    int async_err = 0;
+    int flags = 0;
+    PyObject *offset_src_obj, *offset_dst_obj;
+    static char *keywords[] = {"src", "dst", "count",
+                               "offset_src", "offset_dst", "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, &src, &dst, &count, &offset_src_obj, &offset_dst_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_src_obj == Py_None)
+        p_offset_src = NULL;
+    else {
+        if (!Py_off_t_converter(offset_src_obj, &offset_src))
+            return NULL;
+        p_offset_src = &offset_src;
+    }
+    if (offset_dst_obj == Py_None)
+        p_offset_dst = NULL;
+    else {
+        if (!Py_off_t_converter(offset_dst_obj, &offset_dst))
+            return NULL;
+        p_offset_dst = &offset_dst;
+    }
+
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        ret = copy_file_range(src, p_offset_src, dst, p_offset_dst, 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
diff -r fb70ea8b7b2d configure.ac
--- a/configure.ac	Tue Apr 26 09:31:11 2016 +0300
+++ b/configure.ac	Thu May 12 15:53:41 2016 +0200
@@ -3298,6 +3298,12 @@
       [#include <sys/types.h>
        #include <dirent.h>])
 
+AC_CHECK_DECL(__NR_copy_file_range,
+    AC_DEFINE(HAVE_COPY_FILE_RANGE, 1,
+              Define if you have the 'copy_file_range' syscall.), ,
+    [#include <sys/syscall.h>
+     #include <unistd.h>])
+
 # For some functions, having a definition is not sufficient, since
 # we want to take their address.
 AC_MSG_CHECKING(for chroot)