On Tue, 11 Mar 2003, Oakes King wrote:

> Hi all, I'm writing a multithread web crawler for downloading images from
> the web. Each thread do the same thing: Connect to a web site, seek images
> and download them. And certainly it'll block when connecting to the remote
> server since I use block TCP mothed in each thread. So the problem comes: My
> program allows users to cancel downloading. It's really a headache when the
> thread is blocking since I can not notify that thread to end its work when
> it's downling or trying to build a connection to the remote server. How can
> I close all threads when users' trying to cancel downloading? Should I kill
> the thread in block? That's is the last choice if no other good solution
> since kill a thread will cause many problems, such as memory leak.

There is no (good) way to do that.

My advice is to fire up a new thread to take care of the new job and let the
old one finish its business and when you get control back you close it down
by the rules.

-- 
 Daniel Stenberg -- curl, cURL, Curl, CURL. Groks URLs.
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