Sure it will do if one of the processes needs read access only. Scenario when you need shared rw acces with locking: In the file you have "records" say 30 bytes long, 2 processes are reading/writing these records by: lock-read-unlock or lock-write-unlock . Both processes have to open the file with rw access and the third process can overwrite the locked file. Actually the common method to prevent file from been overwritten is: lock the region outside the file. Such feacure is added to lock/unlock namely for this purpose.
You found the bug in WIN32. In fact the file locked and overwritten hav ALL BYTES ZERO and the length of the copyed file. -- http://mail.python.org/mailman/listinfo/python-list
