file corruption on windows - possible bug

[Fredrik Lundh]

Jeremy Jones wrote:

> #################################
> file_dict = {}
>
> a_list = [("a", "a%s" % i) for i in range(2500)]
> b_list = [("b", "b%s" % i) for i in range(2500)]
> c_list = [("c", "c%s" % i) for i in range(2500)]
> d_list = [("d", "d%s" % i) for i in range(2500)]
>
>
> joined_list = a_list + b_list + c_list + d_list
>
> for key, value in joined_list:
>    outfile = file_dict.setdefault(key, open("%s.txt" % key, "w"))

you do realize that this opens the file again every time, so you end up having
4x2500 file handles pointing to 4 physical files.  that's a bad idea.

if you replace

    outfile = file_dict.setdefault(key, open("%s.txt" % key, "w"))

with

    outfile = file_dict.get(key)
    if outfile is None:
        file_dict[key] = outfile = open("%s.txt" % key, "w")

or, if you prefer,

    try:
        outfile = file_dict[key]
    except KeyError:
        file_dict[key] = outfile = open("%s.txt" % key, "w")

your code won't depend on any undefined behaviour, and will work properly
on all platforms.

</F>