I am creating a downloadaccelerator library Is there any way to know before starting a download from a link weather the server supports resuming downloads/downloading file reange . Because if it does then i ll use multipple connections and download ranges or else i ll download the whole file normally
thank you
Similar to GET header to get the required html page, we have something called as HEAD header.
When you send a HEAD request for an URL we get a set of values for the URL
Example: if you want to know details of http://www.wgz.org/chromatic/perl/IntroTestMore.pdf
Send a HEAD command to the URL, the response will be
Date: Mon, 03 Nov 2008 06:29:09 GMT
Accept-Ranges: bytes
ETag: "156046f-11889-3a578cd2bf2c0"
Server: Apache
Content-Length: 71817
Content-Type: application/pdf
Last-Modified: Thu, 11 Jul 2002 04:53:07 GMT
Client-Date: Mon, 03 Nov 2008 06:29:10 GMT
Client-Peer: 167.168.132.148:8080
Client-Response-Num: 1
Intresting Values: Accept-Ranges, Content-Length
Accept-Ranges: bytes tells that server is ready to give files part by part as requested
More info here: http://www.crazyengineers.com/community/threads/how-does-resume-download-work.7396/