bpo-32146: Add documentation about frozen executables on Unix (GH-5850)

(cherry picked from commit bab4bbb4c9cd5d25ede21a1b8c99d56e3b8dae9d)

Co-authored-by: Bo Bayles <bbayles@gmail.com>

diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 504f3a1c3c33bf8f435b2a99d135548b8e42fdbb..c50625dda32019bc93d6bcea0568bce1f5216031 100644 (file)
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -186,6 +186,13 @@ A library which wants to use a particular start method should probably
 use :func:`get_context` to avoid interfering with the choice of the
 library user.
 
+.. warning::
+
+   The ``'spawn'`` and ``'forkserver'`` start methods cannot currently
+   be used with "frozen" executables (i.e., binaries produced by
+   packages like **PyInstaller** and **cx_Freeze**) on Unix.
+   The ``'fork'`` start method does work.
+
 
 Exchanging objects between processes
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

diff --git a/Misc/NEWS.d/next/Library/2018-02-25-10-17-23.bpo-32146.xOzUFW.rst b/Misc/NEWS.d/next/Library/2018-02-25-10-17-23.bpo-32146.xOzUFW.rst
new file mode 100644 (file)
index 0000000..f071c71
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-02-25-10-17-23.bpo-32146.xOzUFW.rst
@@ -0,0 +1,2 @@
+Document the interaction between frozen executables and the spawn and
+forkserver start methods in multiprocessing.