There are a few issues involved here. The first, of course, is determining the Terms of Service or "Fair Use" of the site in question. Do they disallow screen scraping? Do they have a robots.txt file that disallows your program accessing the files in question? If so, respecting that is important etiquette. For example, you could check out the robots.txt file in the root directory of the White House Web site.

Assuming there are no ethical objections to writing your program, it might be a good idea to contact the Webmaster of the site you are scraping and ask them what an appropriate delay is. As tilly pointed out, if someone is serving CGIs off an old computer at home, even your two second delay could be problematic.

Cheers,
Ovid

New address of my CGI Course.

In reply to Re^3: Ethical issues with screen scraping by Ovid
in thread Use WWW::Mechanize to Download Pictures of Sayuri Anzu by Anonymous Monk

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