"could ildg" wrote: > > so how can I do the binary stuff? > > 8-bit strings contain bytes. > > > I want a encrypt function like below: > > def encrypt(filename,n): > > f = open(filename,"rb+") > > > a=f.read(n) > > b = encrypt(a)
^^^^^^^^Thank you~~,but where is the encrypt defined? oh, I though you asked how to update the first n bytes of a binary file. if you want to XOR the bytes, you can do something like: import array b = array.array("B", a) for i in range(len(b)): b[i] = b[i] ^ 255 b = b.tostring() or b = "".join([chr(ord(c) ^ 255) for c in a]) or some variation thereof. </F> -- http://mail.python.org/mailman/listinfo/python-list