Tracker 4.42

### 4.5.7: NextStep port

There is a known problem: You can't skip patterns forward or backward in quick succession. It will restart the same pattern. This is because of the buffering we have to do, while keeping syncronized with display output. I'll fix it, when I find the time.

There used to be a problem with big endians/little endians machines. It should be solved these days. Look around in ``Arch/NeXT/audio.c`' for `SNDSwapSoundToHost`.

Please double-check that your machine does support audio output, as this is not the case with all NextStep machines.

In case you have a problem that is specific to the NextStep port, you might ask Rolf Grossmann (see Credits).

The NextStep port of tracker was originally done on m68k hardware, but other people have tried it on the other NextStep platforms as well (and submitted patches when necessary).

These are the main changes Rolf had to make, in case someone is interested:

- Added support for sgtty (``old'' BSD) style terminal settings to ``Arch/Unix/ui.c`'. Also cleaned this up and made it architecture independent. Verified that it works on Suns, too.
- Created a new variable `play_ahead` that tells how many buffer blocks are queued before waiting for the sound to actually play. The buffering is required to ensure continous play, even if the program is not running continously (like when you're actually working with the computer). You can set it's value using the port-specific option -play-ahead <n>. I think the default of 5 is a good value and you probably won't need to change it.
- Added call to `SNDSwapSoundToHost` before actually playing the sound, so it should work on NS/intel now.
- Thanks to recent changes to the ``Makefile`' it should even work with NeXT's native make. If you're having problems with it, use GNU make.