## To build:

This entry requires SDL.  See the
FAQ on "[SDL1 and SDL2](../../faq.html#SDL)"
for information on how to install it if you
haven't already.

If you have SDL installed:

``` <!---sh-->
    make
```


## To use:

``` <!---sh-->
    ./jetro
```


## Judges' remarks:

We have seen entries with SDL graphics in the past, now it's time for SDL
sound. This entry can even be run on a computer without a sound card with an
appropriate setting of an environment variable - for that you'll have to dig
into the SDL documentation.

Can you figure out how the notes are encoded and program a different melody?


## Author's remarks:

To compile the entry you need SDL library, which is used only for audio
output. To run the entry make sure you have audio output available. The entry
plays 22KHz 16 bit mono music with a small softsynth. When the music plays,
you can stop the application by pressing enter, as the code will just wait
with one call to `getchar()` before it quits.


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