Am Donnerstag, 3. April 2008 16:25:18 schrieb Timothy J Miller: > That relates to another question I've had--how session and thread safe > are all these architectures (PCSC-lite, OpenSC, & OpenCT)? E.g., if > I'm driving multiple heads off one Linux box, all with their own > readers, how easy would it be for session A to use session B's card?
I don't think there is any thread safety in opensc. why would you need it? not sure, but two different threads should be able to talk to two different card readers (and thus cards) without any issue - so on that level openct should be fine, and pcsc-lite most likely too. note: access to a smart card is serial - one request, one answer. same situation on readers more or less. so if you have several threads, you should make sure only one tries to talk to a smart card/reader at the same time. why anyone would want to use several smart card readers/cards at the same time using several threads - no idea. nothing I would try, even if it works the code was never tested for that. something in pkcs#11 talks about multi threadding, IIRC the question is if you block concurrent access or the library does that itself. but in the end the multi threaded approach is locking&serialization I guess. on that level opensc might be multi threaded, but I'm no expert here. IMHO we have so much trouble with blocking concurrent access by several applications, we need a client/server design with the "server" managing the card for all applications anyway. then the client lib to talk to the server could be safe for multi threaded access - the server won't care much if two threads or two processes talk to it. and it could handle everything serialized - not sure if it is a good idea - or serialize only some access and would need proper multi-threaded code for the rest anyway. but not sure if anyone will every write something like this. Regards, Andreas _______________________________________________ opensc-devel mailing list opensc-devel@lists.opensc-project.org http://www.opensc-project.org/mailman/listinfo/opensc-devel
