[LAU] cancelling I/O with libsndfile

Hi, I'm trying to cancel an ongoing sf_* I/O operation (from another thread of course). I'm finding this extremely unpleasant to implement. * libsndfile sf_read_* and sf_write_* loop until the requested number of frames has been transferred -- so signals are useless, even if I were to disable SA_RESTART behavior * a pthread_cancel() in the middle of I/O seems to mess up the SNDFILE's data structure to the point that it is unusable later on; so besides having to create a new thread after cancelling, I have to re-open the SNDFILE (or manage a pool of back-up SNDFILE's, complete with duplicate fd's) Also, libsndfile doesn't seem to employ a user-space cache like normal C streams (FILE *) -- instead it goes directly to read(2) and write(2). This of course makes it exceedingly inefficient to read 1 frame at a time (due to repetead syscall overhead). So... it's hard to process low-latency dynamic I/O requests with libsndfile. It would be nice if libsndfile could allow short reads and writes via some sf_command parameter. BTW, I've had trouble sending messages to the sndfile-users mailing list (I subscribed, then it still rejected my mails). In any case, since there seems to be no mailing list archive, it doesn't seem like a very trustworthy mailing list. -- Dan