Curious: what libraries do Download manager uses?

[evstevemd]

Hi,
I know of two curl and libtorrent but I was just doing a study on what library/component/whatever you call it, is famous among download managers. I could not get information on FreeDownloadManager, Flashget, Multiget, DownloadThemAll et al.
Would you help me find what libraries do these use, especially for http, ftp, and torrent protocols
Cheers!

[harinath_2007]

I know of two curl and libtorrent

Could you post or share your information regarding that because even i am curious regarding what libraries they use in C/C++ as I have some idea on how to do that in java.

Let me know if you are updated with any information regarding that..

[evstevemd]

Could you post or share your information regarding that because even i am curious regarding what libraries they use in C/C++ as I have some idea on how to do that in java.

Let me know if you are updated with any information regarding that..

I'm still trying to get trade secrets of download managers, so far I have not got one. I will post once I get any.
How does it go with Java?

[harinath_2007]

Well..achieved basic functionality like pause/resume etc..lot more to work like how to manage like increasing/decreasing the bandwidth of download etc..

[evstevemd]

Well..achieved basic functionality like pause/resume etc..lot more to work like how to manage like increasing/decreasing the bandwidth of download etc..

How did you do that!

[Sky Diploma]

If pause and resume is the case. I think I have an explanation for it.

The first time the download manager makes the HTTP request to the server. The server then formulates another HTTP response with the total size of the file and some data.

Once you pause it, maybe the Download Manager keeps track of how much data it has received.

Then when you ask it to resume, it would just formulate another HTTP request. However this request might have an additional attribute(Range). This would specify from which byte the data should be sent.

So all that the manager would then do is to glue the previous data with the new data and VOILA here is the file.

However this would be a rather theoretical explanation.
As far as Libraries are considered. AM ALL EARS as well :).

[evstevemd]

Boost Asio is mentioned in this thread and I will check how does it relate to the Download Manager thing
Also there is C# article on writing DM here may be it can give an idea?