I\'m wondering if the Portable Class Library is even more restricted in functionality than the Compact Framework.
I\'m trying to port a CF/Windows CE app (runs on a
Xamarin has a scanner which will give you a rough idea of the portability of your code: http://scan.xamarin.com/
For some guidance on how to deal with non-portable APIs from PCLs, see my blog post: How to Make Portable Class Libraries Work for You
For file IO in particular, you can try my PCL Storage library.