Merge pull request #2754 from effigies/fix/multiproc37

FIX: Python 2.7-3.7.1 compatible NonDaemonPool

Author: effigies

nipype/pipeline/plugins/legacymultiproc.py

@@ -11,7 +11,7 @@
 
 # Import packages
 import os
-from multiprocessing import Process, Pool, cpu_count, pool
+from multiprocessing import Pool, cpu_count, pool
 from traceback import format_exception
 import sys
 from logging import INFO
@@ -74,23 +74,23 @@ def run_node(node, updatehash, taskid):
     return result
 
 
-class NonDaemonProcess(Process):
-    """A non-daemon process to support internal multiprocessing.
-    """
-
-    def _get_daemon(self):
-        return False
-
-    def _set_daemon(self, value):
-        pass
-
-    daemon = property(_get_daemon, _set_daemon)
-
-
 class NonDaemonPool(pool.Pool):
     """A process pool with non-daemon processes.
     """
-    Process = NonDaemonProcess
+    def Process(self, *args, **kwds):
+        proc = super(NonDaemonPool, self).Process(*args, **kwds)
+
+        class NonDaemonProcess(proc.__class__):
+            """Monkey-patch process to ensure it is never daemonized"""
+            @property
+            def daemon(self):
+                return False
+
+            @daemon.setter
+            def daemon(self, val):
+                pass
+        proc.__class__ = NonDaemonProcess
+        return proc
 
 
 class LegacyMultiProcPlugin(DistributedPluginBase):