[Jens Theisen] > ... > Actually I'm not sure what this optimisation should give you anyway. The > only circumstance under which files with only zeroes are meaningful is > testing, and that's exactly when you don't want that optimisation.
In most cases, a guarantee that reading "uninitialized" file data will return zeroes is a security promise, not an optimization. C doesn't require this behavior, but POSIX does. On FAT/FAT32, if you create a file, seek to a "large" offset, write a byte, then read the uninitialized data from offset 0 up to the byte just written, you get back whatever happened to be sitting on disk at the locations now reserved for the file. That can include passwords, other peoples' email, etc -- anything whatsoever that may have been written to disk at some time in the disk's history. Security weenies get upset at stuff like that ;-) -- http://mail.python.org/mailman/listinfo/python-list
