downloading from two or more torrents to the same file

[alpin]

The other day I opened a torrent and it started downloading into an existing file, Because both torrents had the same file-name embedded in them. I found a few forums with discussions on this problem but no clear answer as to how to behave.

I say that utorrent should do one of the following:

1) notice that I am going to overwrite an existing file, and warn me, so that I can change the directory or file name.

2) If the files are identical, (can this be determined by check-sums ?). Then utorrent could use both torrents simultaneously and write to the same file.

Apparently, at the moment (1.8.2) the writing of the two torrents is NOT synchronized. I do not see why not. After all, it is the same instance of the program. It does have two sources but it can easily determine that it is writing to the same file.

At the moment I am running an experiment. Using two torrents that save to the same file. I think/hope it is exactly the same file. I do not know if I have a way of making sure.

I hope that at some stage one of the two torrents will "notice" the extra data written by the other, and so reach 100% at some stage.

Hope for some answer or remedy soon.

[moogly]

For your experiment, you can compute MD5 to know if files are different or not. Many freewares do that.

[Firon]

µTorrent can't really know if the data is the same, actually.

[moogly]

Anyway maybe uT can detect same filenames and add a number to file or warn the user no? (like a web browser etc)

[alpin]

But uT could compare the MD5 or other CRC and at least when they are different, prevent writing to the same file. Can I find the MD5 looking at a torrent file ?

[Firon]

No, torrents don't use MD5. In fact, torrents don't even store the full hash for the file. They divide the file into smaller chunks and hash those. That's why you can't feasibly do this. It has no real concept of files.