New TemporaryFile implementation for Windows: this doesn't need a
TemproraryFileWrapper wrapper anymore, and should be immune from the
problem that a temp file inherited by a spawned process caused an
attempt to close the temp file in the spawning process to blow
up (the unlink in TemporaryFileWrapper.close() blew up with a
"Permission denied" error because, despite that the temp file got
closed in the spawning process, the spawned process still had it open
by virtue of C-level file descriptor inheritance). In context,
that bug took days to figure out <wink/sigh>.
diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index 51e43b0..99177f5 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -193,8 +193,24 @@
except:
os.close(fd)
raise
+ elif os.name == 'nt':
+ # Windows -- can't unlink an open file, but O_TEMPORARY creates a
+ # file that "deletes itself" when the last handle is closed.
+ # O_NOINHERIT ensures processes created via spawn() don't get a
+ # handle to this too. That would be a security hole, and, on my
+ # Win98SE box, when an O_TEMPORARY file is inherited by a spawned
+ # process, the fd in the spawned process seems to lack the
+ # O_TEMPORARY flag, so the file doesn't go away by magic then if the
+ # spawning process closes it first.
+ flags = (os.O_RDWR | os.O_CREAT | os.O_EXCL |
+ os.O_TEMPORARY | os.O_NOINHERIT)
+ if 'b' in mode:
+ flags |= os.O_BINARY
+ fd = os.open(name, flags, 0700)
+ return os.fdopen(fd, mode, bufsize)
else:
- # Non-unix -- can't unlink file that's still open, use wrapper
+ # Assume we can't unlink a file that's still open, or arrange for
+ # an automagically self-deleting file -- use wrapper.
file = open(name, mode, bufsize)
return TemporaryFileWrapper(file, name)