The warning works for me now.  That's much better than opening a browser window, thanks a lot.  I am still a total noob at flash, so I don't have more info about the semantics at this point.

Hi,

you are right, my description was incomplete, I didn't notice this earlier.  You need to click a second time after the target file is loaded.  See the debug output below.

BTW, this indicates another bug: Gnash should initiate the "print:" action as soon as the file is loaded.  It does display the "Printing info sheet" text above the button for a split second, but it does not open the print: URL.  Strange.

14:19:12: get url: target=tech_sheet, url=file:///home/marcus/gnu/gnash/flashkit/013-custom-print/tech_sheet.swf (tech_sheet.swf)
14:19:12: getURL2 target load
14:19:21: get url: target=tech_sheet, url=file:///home/marcus/gnu/gnash/flashkit/013-custom-print/tech_sheet.swf (tech_sheet.swf)
14:19:21: getURL2 target load
14:19:21:  movie already in library
14:19:21: get url: target=tech_sheet, url=file:///home/marcus/gnu/gnash/flashkit/013-custom-print/print: (print:)
14:19:21: Launching URL... firefox -remote "openurl(file:///home/marcus/gnu/gnash/flashkit/013-custom-print/print:)"

Thanks,
Marcus

Have a look at
http://images2.flashkit.com/tutorials/Getting_Started/Customis-Eddie_Ca-31/ad_banner.swf

This little flash (version 4) file has a customized print button.  When one presses the print button at the end of the animation (be sure to check out bug #17913 if you can't find it, ie minimize the viewport), gnash tries to open BASE-URL+"print:" in the browser.  This of course leads to a File Not Found error.

Suggested fix: Catch the "print:" special URL in the URL handler and in case it is detected, do not open the URL, but invoke a print-handler (which for now I suppose would just print a debug log message and ignores the request).