iphone/mac - how to download files with AsyncSocket

Question

Hi guys,

I have a remote server with some files. I want to use AsyncSocket to download a file, chunk by chunk. I would like to send HTTP requests with ranges through the socket and get the appropriate chunks of data. I understand how to do this on localhost, but not from a remote server. I really don't know how to use the connectToHost and acceptOnInterface (previously acceptOnAddress) methods.

Please help

Thanks

Answer 1

AsyncSocket is a general purpose data connection. If you want it to talk HTTP, you'll need to code the HTTP portion yourself. You probably don't actually want this; NSURLConnection should do what you want, provided the server supports it.

What you're asking for is the Range: header in HTTP. See 14.35.2 in RFC2616. You just need to add this header to your NSURLRequest. Again, this presumes that the server you're talking to supports this (you need to check the Accept-Ranges: header in the response).

There's a short article with example code about this at Surgeworks.

You should also look at ASIHTTPRequest, which includes resumable downloads and download progress delgates, and can likely be adapted to doing partial downloads. It may already have the solution to the specific issue you're trying to solve.