I use mapnik2 under windows,when i use the style
ShieldSymbolizer base="E:\test" file ="test.png"
ShieldSymbolizer base="E:/test" file ="test.png"
i get the error
and the map does not show the marker
but ShieldSymbolizer file ="E:\test\test.png" the result is right
Interesting, thanks for the report.
by the way, i used windows 7
Looking into the code, I guess you should define a filesource in <Map>
(I suppose current win understand forward slashes too) and then use
<ShieldSymbolizer base="images" file="test.png">
(and it kind of makes sense, would be useless to have actual path in base, this way you can take images from another place by changing just the FileSource)
Note: didn't find it documented, so there certainly is space for improvement ;)