On Fri, Apr 8, 2016 at 3:53 PM, Adam Goode <agoode@xxxxxxxxxx> wrote: > On Fri, Apr 8, 2016 at 1:56 PM, Martin Koegler <martin.koegler@xxxxxxxxx> > wrote: > >> On Fri, Apr 08, 2016 at 11:21:57AM -0400, Adam Goode wrote: >> > So there are 2 alternatives I can think of: >> > >> > option 1: introduce snd_seq_client_info_get_pid_2() and leave the >> existing >> > function alone. This new function can return a new constant, >> > SND_SEQ_CLIENT_INFO_PID_UNKNOWN for missing kernel support. Same for >> card. >> > option 2: introduce snd_seq_client_info_pid_known() that returns a bool >> if >> > there is kernel support. Same for card. >> >> I wouldn't implement option 1. Using that methode for API changes will >> result in lots of rarely used functions. >> >> Chrome will probable need that information to enable a fallback-code - if >> a application has no fallback code, >> it has no need for different returncodes. In a few years, most >> distributions will likely ship kernel including that functions, >> so there is no need to for fallback-code and the kernel support check any >> more. >> >> Why not a snd_seq_client_info_get_capatibilites() returing bit flags: >> .._CAP_CARD_NUMBER | .._CAP_PID ? >> >> > This approach is fine by me as well, though it does introduce more > constants and bitwise logic. > > Since returning to this problem after a while, I've realized that we don't need any changes at all to alsa-lib. This test is equivalent to what is needed: snd_seq_get_client_info(seq, info); // get our client's info bool client_pid_supported = snd_seq_client_info_get_pid(info) != -1; // do we know our own PID? It might be helpful to put this into the documentation, but otherwise I think this is fine. Thanks, Adam _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
