Patch #1537850: tempfile.NamedTemporaryFile now has a "delete" parameter

which can be set to False to prevent the default delete-on-close
behavior.

Doc/lib/libtempfile.tex

@@ -53,7 +53,7 @@ The \var{dir}, \var{prefix} and \var{suffix} parameters are passed to
 \begin{funcdesc}{NamedTemporaryFile}{\optional{mode=\code{'w+b'}\optional{,
                                      bufsize=\code{-1}\optional{,
                                      suffix\optional{, prefix\optional{,
-                                     dir}}}}}}
+                                     dir\optional{, delete}}}}}}}
 This function operates exactly as \function{TemporaryFile()} does,
 except that the file is guaranteed to have a visible name in the file
 system (on \UNIX, the directory entry is not unlinked).  That name can
@@ -61,7 +61,10 @@ be retrieved from the \member{name} member of the file object.  Whether
 the name can be used to open the file a second time, while the
 named temporary file is still open, varies across platforms (it can
 be so used on \UNIX; it cannot on Windows NT or later).
+If \var{delete} is true (the default), the file is deleted as soon as
+it is closed.
 \versionadded{2.3}
+\versionadded[The \var{delete} parameter]{2.6}
 \end{funcdesc}
 
 \begin{funcdesc}{mkstemp}{\optional{suffix\optional{,

Lib/tempfile.py

@@ -372,10 +372,11 @@ class _TemporaryFileWrapper:
     remove the file when it is no longer needed.
     """
 
-    def __init__(self, file, name):
+    def __init__(self, file, name, delete=True):
         self.file = file
         self.name = name
         self.close_called = False
+        self.delete = delete
 
     def __getattr__(self, name):
         file = self.__dict__['file']
@@ -400,23 +401,25 @@ class _TemporaryFileWrapper:
             if not self.close_called:
                 self.close_called = True
                 self.file.close()
-                self.unlink(self.name)
+                if self.delete:
+                    self.unlink(self.name)
 
         def __del__(self):
             self.close()
 
 def NamedTemporaryFile(mode='w+b', bufsize=-1, suffix="",
-                       prefix=template, dir=None):
+                       prefix=template, dir=None, delete=True):
     """Create and return a temporary file.
     Arguments:
     'prefix', 'suffix', 'dir' -- as for mkstemp.
     'mode' -- the mode argument to os.fdopen (default "w+b").
     'bufsize' -- the buffer size argument to os.fdopen (default -1).
+    'delete' -- whether the file is deleted on close (default True).
     The file is created as mkstemp() would do it.
 
     Returns an object with a file-like interface; the name of the file
     is accessible as file.name.  The file will be automatically deleted
-    when it is closed.
+    when it is closed unless the 'delete' argument is set to False.
     """
 
     if dir is None:
@@ -429,12 +432,12 @@ def NamedTemporaryFile(mode='w+b', bufsize=-1, suffix="",
 
     # Setting O_TEMPORARY in the flags causes the OS to delete
     # the file when it is closed.  This is only supported by Windows.
-    if _os.name == 'nt':
+    if _os.name == 'nt' and delete:
         flags |= _os.O_TEMPORARY
 
     (fd, name) = _mkstemp_inner(dir, prefix, suffix, flags)
     file = _os.fdopen(fd, mode, bufsize)
-    return _TemporaryFileWrapper(file, name)
+    return _TemporaryFileWrapper(file, name, delete)
 
 if _os.name != 'posix' or _os.sys.platform == 'cygwin':
     # On non-POSIX and Cygwin systems, assume that we cannot unlink a file

Lib/test/test_tempfile.py

@@ -561,11 +561,12 @@ test_classes.append(test_mktemp)
 class test_NamedTemporaryFile(TC):
     """Test NamedTemporaryFile()."""
 
-    def do_create(self, dir=None, pre="", suf=""):
+    def do_create(self, dir=None, pre="", suf="", delete=True):
         if dir is None:
             dir = tempfile.gettempdir()
         try:
-            file = tempfile.NamedTemporaryFile(dir=dir, prefix=pre, suffix=suf)
+            file = tempfile.NamedTemporaryFile(dir=dir, prefix=pre, suffix=suf,
+	                                       delete=delete)
         except:
             self.failOnException("NamedTemporaryFile")
 
@@ -599,6 +600,22 @@ class test_NamedTemporaryFile(TC):
         finally:
             os.rmdir(dir)
 
+    def test_dis_del_on_close(self):
+        # Tests that delete-on-close can be disabled
+        dir = tempfile.mkdtemp()
+	tmp = None
+        try:
+            f = tempfile.NamedTemporaryFile(dir=dir, delete=False)
+            tmp = f.name
+            f.write('blat')
+            f.close()
+            self.failUnless(os.path.exists(f.name),
+                        "NamedTemporaryFile %s missing after close" % f.name)
+        finally:
+            if tmp is not None:
+                os.unlink(tmp)
+            os.rmdir(dir)
+
     def test_multiple_close(self):
         # A NamedTemporaryFile can be closed many times without error
 

Misc/ACKS

@@ -430,6 +430,7 @@ Mike Meyer
 Steven Miale
 Trent Mick
 Chad Miller
+Damien Miller
 Roman Milner
 Dom Mitchell
 Doug Moen

Misc/NEWS

@@ -168,6 +168,10 @@ Core and builtins
 Library
 -------
 
+- Patch #1537850: tempfile.NamedTemporaryFile now has a "delete" parameter
+  which can be set to False to prevent the default delete-on-close
+  behavior.
+
 - Patch #1581073: add a flag to textwrap that prevents the dropping of
   whitespace while wrapping.