view docs/html/sdlcdstatus.html @ 2866:e532417a6977

Fixed SDL 1.2 compatibility problem. The API specifies that SDL_OpenAudio() will fill out the 'desired' audio spec with the correct samples and size set by the driver. This value is important since it may be used by applications that size audio buffers, etc. However, we want to allow advanced applications to call SDL_OpenAudioDevice() which gets passed a const 'desired' parameter, and have the correct data filled into the 'obtained' parameter, possibly allowing or not allowing format changes. So... 'obtained' becomes the audio format the user callback is expected to use, and we add flags to allow the application to specify which format changes are allowed. Note: We really need to add a way to query the 'obtained' audio spec.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 13 Dec 2008 06:36:47 +0000
parents 355632dca928
children
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><H1
><A
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>SDL_CDStatus</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN7308"
></A
><H2
>Name</H2
>SDL_CDStatus&nbsp;--&nbsp;Returns the current status of the given drive.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN7311"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
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NAME="AEN7312"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>CDstatus <B
CLASS="FSFUNC"
>SDL_CDStatus</B
></CODE
>(SDL_CD *cdrom);</CODE
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>/* Given a status, returns true if there's a disk in the drive */
#define CD_INDRIVE(status)      ((int)status &#62; 0)</PRE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7319"
></A
><H2
>Description</H2
><P
>This function returns the current status of the given drive. Status is described like so:
<PRE
CLASS="PROGRAMLISTING"
>typedef enum {
  CD_TRAYEMPTY,
  CD_STOPPED,
  CD_PLAYING,
  CD_PAUSED,
  CD_ERROR = -1
} CDstatus;</PRE
></P
><P
>If the drive has a CD in it, the table of contents of the CD and current
play position of the CD will be stored in the SDL_CD structure.</P
><P
>The macro <TT
CLASS="LITERAL"
>CD_INDRIVE</TT
> is provided for convenience, 
and given a status returns true if there's a disk in the drive.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
><TT
CLASS="FUNCTION"
>SDL_CDStatus</TT
> also updates the <A
HREF="sdlcd.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_CD</SPAN
></A
> structure passed to it.</P
></BLOCKQUOTE
></DIV
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CLASS="REFSECT1"
><A
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></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>int playTrack(int track)
{
  int playing = 0;

  if ( CD_INDRIVE(SDL_CDStatus(cdrom)) ) {
  /* clamp to the actual number of tracks on the CD */
    if (track &#62;= cdrom-&#62;numtracks) {
      track = cdrom-&#62;numtracks-1;
    }

    if ( SDL_CDPlayTracks(cdrom, track, 0, 1, 0) == 0 ) {
      playing = 1;
    }
  }
  return playing;
}</PRE
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><A
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><H2
>See Also</H2
><P
><A
HREF="sdlcd.html"
><TT
CLASS="FUNCTION"
>SDL_CD</TT
></A
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