Hi below,
now I've tried your call to OpenBook( ... ) myself on emulator.
Indeed inkview calls the pdfviewer.app indirectly via "system/config/extensions.cfg", where the file extensions (like .pdf) are all assigned to the handling .app-programs.
But unfortunately the pdfviewer.app is not available in the emulator.
And before you try to copy "pdfviewer.app" from your PB603 to the emulator's "/system/bin", be warned, that you would have to use a version of "pdfviewer.app", that is compiled and linked for "i386" (for "emu", not for device). You could compile and build it yourself, because the source-code for "pdfviewer-pb" is available on the internet (
https://pocketbook-free.svn.sourcefo.../pdfviewer-pb/) - but i expect problems with libraries and so on, if you really try.
If anyone (perhaps you?) would do this work to compile and build all available standard-apps for emulator, I would be glad, if you post them here.