Merge with 3.1

3 files changed, 9 insertions, 1 deletions

diff --git a/Lib/multiprocessing/__init__.py b/Lib/multiprocessing/__init__.py
index adad63063c..deb031c367 100644
--- a/Lib/multiprocessing/__init__.py
+++ b/Lib/multiprocessing/__init__.py
@@ -115,8 +115,11 @@ def cpu_count():
         except (ValueError, KeyError):
             num = 0
     elif 'bsd' in sys.platform or sys.platform == 'darwin':
+        comm = '/sbin/sysctl -n hw.ncpu'
+        if sys.platform == 'darwin':
+            comm = '/usr' + comm
         try:
-            with os.popen('sysctl -n hw.ncpu') as p:
+            with os.popen(comm) as p:
                 num = int(p.read())
         except ValueError:
             num = 0
diff --git a/Misc/ACKS b/Misc/ACKS
index 89382672da..5c1bdc5904 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -624,6 +624,7 @@ Tim Northover
 Joe Norton
 Neal Norwitz
 Michal Nowikowski
+Steffen Daode Nurpmeso
 Nigel O'Brian
 Kevin O'Connor
 Tim O'Malley
diff --git a/Misc/NEWS b/Misc/NEWS
index 78442fac2f..bd21c5c71c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -43,6 +43,10 @@ Library
 - Issue #11133: fix two cases where inspect.getattr_static can trigger code
   execution. Patch by Daniel Urban.
 
+- Issue #11569: use absolute path to the sysctl command in multiprocessing to
+  ensure that it will be found regardless of the shell PATH. This ensures
+  that multiprocessing.cpu_count works on default installs of MacOSX.
+
 - Issue #11501: disutils.archive_utils.make_zipfile no longer fails if zlib is
   not installed. Instead, the zipfile.ZIP_STORED compression is used to create
   the ZipFile. Patch by Natalia B. Bidart.