arts: backed out audio capture support. Turns out that libartsc isn't thread-safe, so if we run a capture and playback device at the same time, it often crashes in arts's internal event loop. We could throw mutexes around the read/write calls, but these are meant to block, so one device could cause serious latency and stutter in the other. Since this audio target isn't in high-demand (Ubuntu hasn't offered a libartsc package for years), I'm just backing out the capture support. If someone needs it, they can pull it out of the revision history.

dummy audio: Patched to compile.

dummy audio: Implemented dummy audio capture support. :)

bsdaudio: first shot at audio capture support! (untested, uncompiled...for now.)

bsdaudio: this appears to be using the wrong variable...? (We probably never noticed because this is meant to block until it fully writes a buffer, and would only trigger an issue if we had a short write that wasn't otherwise an error condition.)

arts: Patched to (maybe) compile.

arts: implemented audio capture support. (completely untested! Not even compiled!!).

alsa: capture devices don't need a mixbuf allocated.

testaudiocapture: made test app interactive. (hold down mouse/finger to record, then it plays back what it heard. Repeat.)

coreaudio: Implemented audio capture for iOS.