SF bug 128713: type(mmap_object) blew up on Linux.

3 files changed, 12 insertions, 2 deletions

diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index 8ac707d..3ad6d7c 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -89,6 +89,7 @@ elif os.name == 'mac':
 else:
     template = 'tmp' # XXX might choose a better one
 
+_pidcache = {}
 def gettempprefix():
     """Function to calculate a prefix of the filename to use.
 
@@ -96,9 +97,15 @@ def gettempprefix():
     notion, so that concurrent processes don't generate the same prefix.
     """
 
-    global template
     if template is None:
-        return '@' + `os.getpid()` + '.'
+        p = os.getpid()
+        t = _pidcache.get(p, 0)
+        if t:
+            return t
+        if len(_pidcache) > 100:    # stop unbounded growth
+            _pidcache.clear()
+        t = _pidcache[p] = '@' + `p` + '.'
+        return t
     else:
         return template
 
diff --git a/Lib/test/output/test_mmap b/Lib/test/output/test_mmap
index 24e28f8..ce2c823 100644
--- a/Lib/test/output/test_mmap
+++ b/Lib/test/output/test_mmap
@@ -1,4 +1,5 @@
 test_mmap
+<type 'mmap'>
   Position of foo: 1.0 pages
   Length of file: 2.0 pages
   Contents of byte 0: '\000'
diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index d07e4c6..7c49cf2 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -18,6 +18,8 @@ def test_both():
     f.close()
 
     # Simple sanity checks
+
+    print type(m)  # SF bug 128713:  segfaulted on Linux
     print '  Position of foo:', string.find(m, 'foo') / float(PAGESIZE), 'pages'
     assert string.find(m, 'foo') == PAGESIZE