if((tgt=check_header(Path::Path("/usr/include/c++/4.1.2")/fn)))
return tgt;
for(list<string>::const_iterator j=path.begin(); j!=path.end(); ++j)
if((tgt=check_header(Path::Path("/usr/include/c++/4.1.2")/fn)))
return tgt;
for(list<string>::const_iterator j=path.begin(); j!=path.end(); ++j)