cmDspBuiltIn.c : The AudioFileOut object no longer creates an output

file when the object is created. It now waits until it is sent an
'open' symbol to create the audio output file.

If the AudioFileOut object is sent a directory rather than a file then
it automatically generates a file name in the given directory.

dsp/cmDspBuiltIn.c

   cmAudioFileH_t afH;
   unsigned       openSymId;
   unsigned       closeSymId;
+  const cmChar_t* afn;
 } cmDspAudioFileOut_t;
 
 cmDspRC_t _cmDspAudioFileOutCreateFile( cmDspCtx_t* ctx, cmDspInst_t* inst, unsigned chCnt )
 {
-  cmDspRC_t rc = kOkDspRC;
+  cmDspRC_t            rc = kOkDspRC;
   cmDspAudioFileOut_t* p  = (cmDspAudioFileOut_t*)inst;
   const cmChar_t*      fn = cmDspStrcz(inst,kFnAofId);
 
   if(cmAudioFileIsValid(p->afH) )
     cmAudioFileDelete(&p->afH);
 
+  // if the supplied audio file name is actually a directory name then generate a file name
+  if( cmFsIsDir(fn) )
+  {
+    cmMemPtrFree(&p->afn);
+
+    if( cmFsGenFn(fn,"recd","aiff",&p->afn) != kOkFsRC )
+      return cmDspInstErr(ctx,&p->inst,kFileSysFailDspRC,"An output audio file name could not be generated.");
+    
+    fn = p->afn;
+  }
+
   if( cmAudioFileIsValid(p->afH =  cmAudioFileNewCreate(fn, cmDspSampleRate(ctx), p->bits, chCnt, &rc, ctx->rpt )) == false )
     rc = cmDspClassErr(ctx,inst->classPtr,kVarArgParseFailDspRC,"The output audio file '%s' create failed.",fn);
 
 {
   cmDspVarArg_t args[] =
   {
-    { "fn",    kFnAofId,    0,   0, kInDsvFl | kStrzDsvFl   | kReqArgDsvFl, "Audio file name"},
+    { "fn",    kFnAofId,    0,   0, kInDsvFl | kStrzDsvFl   | kReqArgDsvFl, "Audio file or directory name"},
     { "chs",   kChCntAofId, 0,   0, kInDsvFl | kUIntDsvFl   | kReqArgDsvFl, "Channel count"}, 
     { "gain0", kGain0AofId, 0,   0, kInDsvFl | kDoubleDsvFl | kOptArgDsvFl, "Output gain 0 multiplier"},  
     { "gain1", kGain1AofId, 0,   0, kInDsvFl | kDoubleDsvFl | kOptArgDsvFl, "Output gain 1 multiplier"},
   p->smpCnt = cmDspSamplesPerCycle(ctx) * chCnt;
   p->smpBuf = cmLhResizeN(ctx->lhH, cmSample_t, p->smpBuf, p->smpCnt);
   
-  rc = _cmDspAudioFileOutCreateFile( ctx, inst, chCnt );
+  //rc = _cmDspAudioFileOutCreateFile( ctx, inst, chCnt );
 
   return rc;
 } 
   cmSample_t*          chArray[chCnt];
   unsigned             i,j;
 
+  if(!cmAudioFileIsValid(p->afH) )
+    return rc;
+
+
   for(i=0,j=0; i<chCnt; ++i)
   {
     unsigned          chVarId = i == 0 ? kIn0AofId : kIn1AofId;     // get audio buf var id for this ch
     {
       cmSample_t gain = cmDspSample(inst,i==0?kGain0AofId:kGain1AofId); // get ch gain
     
-      chArray[j] = cmDspAudioBuf(ctx,inst,chVarId,i);                   // get incoming audio buf ptr
+      chArray[j] = cmDspAudioBuf(ctx,inst,chVarId,0);                   // get incoming audio buf ptr
 
       if( gain != 1.0 )
         cmVOS_MultVVS(chArray[j], iSmpCnt, chArray[j], gain);           // apply gain
   if(cmAudioFileIsValid(p->afH) )
     cmAudioFileDelete(&p->afH);
 
+  cmMemPtrFree(&p->afn);
+
   return kOkDspRC;
 }