如何从 Linux 上运行的 Free Pascal 应用程序播放 wav 文件？

program PlayWav;

{$mode objfpc}{$H+}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SDL2, SDL2_mixer;

var
  audioSpec: TSDL_AudioSpec;
  audioBuf: PUInt8;
  audioLen: UInt32;

  // 加载 wav 文件并返回音频缓冲区
  function LoadWav(const filename: string; out audioBuf: PUInt8; out audioLen: UInt32): TSDL_AudioSpec;
  var
    wavSpec: TSDL_AudioSpec;
    wavBuf: PUInt8;
  begin
    if SDL_LoadWAV(PChar(filename), wavSpec, wavBuf, audioLen) = nil then
      raise Exception.Create('无法加载 wav 文件');

    audioBuf := wavBuf;
    Result := wavSpec;
  end;

begin
  if SDL_Init(SDL_INIT_AUDIO) <> 0 then
    raise Exception.Create('无法初始化 SDL');

  try
    audioSpec := LoadWav('example.wav', audioBuf, audioLen);

    if Mix_OpenAudio(audioSpec.freq, audioSpec.format, audioSpec.channels, audioSpec.samples) <> 0 then
      raise Exception.Create('无法打开音频设备');

    try
      if Mix_PlayChannel(0, PMix_Chunk(audioBuf), 0) = -1 then
        raise Exception.Create('无法播放 wav 文件');

      while Mix_Playing(0) = 1 do
        SDL_Delay(100);

    finally
      Mix_CloseAudio();
    end;

  finally
    SDL_Quit();
  end;
end.