Issue 365 / wait(): cannot make the PID reuse check on Windows as we can determine the exit code also from a dead process.

2 files changed, 14 insertions, 8 deletions

diff --git a/HISTORY b/HISTORY
index 0d1d833c..69b95c28 100644
--- a/HISTORY
+++ b/HISTORY
@@ -44,8 +44,10 @@ BUG FIXES
  * #353: [OSX] get_users() returns an empty list on OSX 10.8.
  * #356: Process.parent now checks whether parent PID has been reused in which
          case returns None.
- * #365: Process wait() and set_nice() methods should check PID has not been
-         reused by another process.
+ * #365: [UNIX] Process.wait() should check PID has not been reused by another
+         process.
+ * #365: Process.set_nice() should check PID has not been reused by another
+         process.
 
 API CHANGES
 
diff --git a/psutil/__init__.py b/psutil/__init__.py
index 720c0d12..1d444fcb 100644
--- a/psutil/__init__.py
+++ b/psutil/__init__.py
@@ -780,13 +780,17 @@ class Process(object):
     def wait(self, timeout=None):
         """Wait for process to terminate and, if process is a children
         of the current one also return its exit code, else None.
-        It also makes sure this process PID has not been reused by
-        another process. If that's the case returns immediately.
+        On UNIX it first makes sure this process PID has not been reused by
+        another process in which case returns immediately.
         """
-        if self.is_running():
-            if timeout is not None and not timeout >= 0:
-                raise ValueError("timeout must be a positive integer")
-            return self._platform_impl.process_wait(timeout)
+        if timeout is not None and not timeout >= 0:
+            raise ValueError("timeout must be a positive integer")
+        # cannot check PID reuse on Windows as we're able to determine
+        # exit code also from a dead process
+        if os.name == 'posix':
+            if not self.is_running():
+                return
+        return self._platform_impl.process_wait(timeout)
 
     # --- deprecated API