Hi, I'm having now my first contact with the pipe framework, an have some comments about it that might be of interest to the core developers:
While the documentation is overall *great*, I fould it a bit lacking regarding the pipes. Would be good to have some examples of general usage. As far as I can tell, there is no mention of the usage of P_MSGPTR and P_MSGSIZE. I had to learn about them in the headers. At first sight, the rt_pipe_send call is confusing: why should I pass the data size since it is supposed to be embedded in the RT_PIPE_MSG structure?. This is what I first did: RT_PIPE_MSG *m = rt_pipe_alloc(sizeof(mystruct)); P_MSGPTR(m) = &mystruct; P_MSGSIZE(m) = sizeof(mystruct) rt_pipe_send(&mypipe, m, sizeof(mystruct), P_NORMAL); Which is obviously wrong. Please correct me if I'm wrong: P_MSGPTR and P_MSGSIZE are intended not to be used as an lvalue (is there a way to define these macros to generate a compile error if they are?). So, the correct way would be something like this (again, correct me if I'm wrong):: RT_PIPE_MSG *m = rt_pipe_alloc(sizeof(mystruct_t)); mystruct_t *p = (mystruct_t *)P_MSGPTR(m); p->whatever1 = X; p->whatever2 = X; rt_pipe_send(&mypipe, m, sizeof(mystruct_t), P_NORMAL); If this is correct, why do I have to specify the size of mystruct_t *twice*. Can't it be initialized by rt_pipe_alloc ?. Nacho. _______________________________________________ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
