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Lisp Sounds
Volume Number:7
Issue Number:3
Column Tag:Lisp Listener

Related Info: Sound Manager Resource Manager

The Sound Manager With Lisp

By Michael S. Engber, Evanston, IL

Using the Sound Manager from LISP

Introduction

This article develops code to play ‘snd ‘ resources asynchronously from Macintosh Allegro Common LISP (MACL) version 1.3. The culmination of these efforts is a macro, with-sound (Ala the standard Common LISP macro, with-open-files), which plays a sound while its body executes. In addition, snd-p and snd-halt, allow you to determine if the sound is still playing and to halt it.

No attempt is made here to teach LISP. The target audience is MACL users who need parts of the ToolBox which MACL doesn’t provide a high level LISP interface to. To this end, I will start out by exploring MACL’s trap and record definition mechanisms and then use them to squeeze some basic functionality from the Sound Manager. Experienced trap users can skip to the last half of the article.

Stack Trap Calls

MACL provides a pre-defined object library that lets you create and use windows, dialog boxes, menus, and most of QuickDraw. They’ve done a pretty good job and it’s pretty well documented in the manual. Someone who knows LISP, but not Mac programming, can sit down, learn their object system, and create an amazingly sophisticated user interface pretty easily. There is no need to deal with events, MACL takes care of that for you. Menus, dialog items, etc., are defined as objects to which you attach action functions. When your menu item gets selected or your dialog item is clicked, its action function gets called.

Unfortunately, if your application get complicated enough, you will probably need parts of the ToolBox MACL’s object library doesn’t include. Upon reading the manual, you’re directed to the rather intimidating trap calls chapter for general info and to Inside Macintosh for the details. Most users take one look and conclude that their program didn’t really need that feature after all. But eventually, rationalization won’t cut it anymore and it’s time to start using traps.

To start with, you need to load in traps.Lisp. This is best accomplished by putting (require ‘traps) in your code. What traps.Lisp does, is associate ToolBox call names and their corresponding trap words. It creates macros that allow you to call a function like OpenResFile by using a mnemonic macro name like _OpenResFile instead of its trap word, #xA997. traps.Lisp contains most of the ToolBox calls you’d normally use. I can only recall running into omissions a few times. If _OpenResFile wasn’t listed in traps.Lisp, it can still be accessed if you know its trap word. You could either add this info to traps.Lisp, or use the general trap calling mechanism which uses trap words rather than their mnemonic names. I’ve glossed over a few points, like the fact that there are stack based traps and register based traps and that there are functions like GetVol for which there are no traps. At this point its probably best to just dig right in. Here’s an code showing a function and a procedure call, GetResource and DetachResource.

;1

(setf my-handle  (_GetResource :ostype “ICON” :word 50 :ptr))(_DetachResource 
:ptr my-handle)

For each argument the ToolBox call takes, you pass a pair <type value> of arguments to the trap macro. The type is a keyword, :word, :long, :ptr, :ostype. The value is the value you actually want passed. In addition, for functions, the last argument of the trap call is a keyword giving the type of the return value.

You might have noticed that the aforementioned four choices for argument types don’t seem sufficient to cover the wealth of types used in Inside Macintosh. With a bit of creative explanation, they actually are. The first thing you have to learn is what ToolBox calls really want passed as arguments. This can be simply expressed in Pascal:

{2}

if (the argument is a var parameter) 
 then pass a pointer to the argument
 else if (the argument size > 4 bytes) 
 then pass a pointer to the argument
 else pass the value of the argument

C and assembly language programmers already live by these rules. Pascal programmers may be scratching their heads right now since the Pascal compiler take care of all this. Trap calls are more akin to assembly language than LISP, so start thinking about argument passing at a lower level. Basically, either you pass a pointer to the argument or you pass its value, in which case you choose one of the 3 value types depends mainly on the size of the argument. Some basic guidelines are summarized in a table.

Unfortunately, the arguments to trap macros are not specified in traps.Lisp. It’s your responsibility to look them up in, Inside Macintosh. No argument checking (type, order, or number) is done and if you mess up MACL usually crashes. No diagnostic error message, just that all too familiar, “Allegro Common LISP has unexpectedly quit.”

Table 1. Stack Trap Argument Types

Notes on Table 1:

• One thing to note is that when points are passed by value they are passed as longints. This is because point records are only four bytes in size. This is an easy thing to forget (ask any C programmer). MACL provides some convenient functions; make-point, point-h, and point-v, to help convert points. from and to their longint form. They also provide the macro read character #@ to help you write legible point literals. This means #@(10 50) reads in as a longint corresponding to the point with the coordinates, 10 horizontal and 50 vertical.

• When boolean values are returned you should check their value by interrogating their eighth bit instead of just checking for a non-zero value. Even though booleans (and chars too) require only one byte, you still pass and receive a whole two byte word. If some of the unused high bits are set, the value returned will be non-zero regardless of whether true or false was returned. It’s easy enough to test bit 8 with the Common LISP logbitp function. When passing boolean values to functions, use -1 for true and 0 for false.

• When longints are passed and returned, only 31 bits are used (sign extension is performed so the sign of the value won’t change). This is because MACL uses the high bit to distinguish pointers from fixnums. At first this sounds like a terrible imposition, but it only is a problem when the value represents a very large unsigned value. So most of the time this won’t affect you, but once in a while it will cause subtle bugs. I was recently bitten while using GetTime and IUDateString. The seconds parameters to these routines are treated as unsigned values and the current date (in seconds) is large enough to have the high bit set. The work around is to treat a long as two consecutive words. Ugly, but at least you can get the job done.

• There is a rather subtle problem with :ostype’s. They need to actually have a string or keyword literal, not something that evaluates to a string or keyword. For example:

;3

(defun get-rsrc (type id) (_GetResource :ostype type :word id))

This doesn’t work because of type. There is no problem with id evaluating to an integer, it’s just :ostype’s that have this problem. This is something that is supposed to fixed in the next version of MACL. For now, I use macro’s to avoid this gotcha. Very few ToolBox calls use :ostype’s so just file this tidbit away somewhere.

Register Trap Calls

If you look carefully at traps.Lisp you’ll see it’s divided into two parts, stack traps and register traps. This is because some ToolBox calls expect their arguments in registers instead of on the stack. This is something that’s normally hidden from both C and Pascal programmers. You’ll need to look up in Inside Macintosh which argument goes in which register and which register contains the return value. Instead of using type keywords, use register name keywords Here’s some examples:

;4

(setf my-ptr (_NewPtr :d0 20 :a0)  ;get a 20 byte block(_DisposPtr :a0 
my-ptr :d0)        ;carelessly discard the return value

Fortunately, traps.Lisp defines stack and register traps differently enough so if you mess up and call a register trap using stack trap conventions MACL catches it. I wouldn’t exactly say it diagnoses the problem, it just gives you the cryptic error message like the one shown below, but at least it doesn’t crash on you.

> Error: :long is not a valid argument to nil> While executing: #<An 
Anonymous Compiled-function>

Passing Pointers to Trap Calls

The above discussion glossed over how you obtain pointers to LISP object. There’s know address operator like & in C or @ in MacPascal. The answer is, you don’t. “Remember this, never forget this:” never use a LISP regular object as a :ptr value. LISP objects are not of this world, they have deep underlying structure and the ToolBox can’t grok them. So what do you do? You allocate some space, stuff the desired value in, and send off this “real” pointer.

Don’t’ despair! The MACL designers, in their infinite wisdom, took pity on us mortals and provided three rather convenient mechanisms for doing this. These three special forms automatically allocate and deallocate the space for you, saving you from much pain and fragmented memory. They work much like our old friend, let Variables are defined and initialized for use within their body.

with-pstrs/with-returned-pstrs - These are for allocating and initializing strings. The with-returned-pstrs form is for used when the call will returns a value. It allocates a full 256 bytes to handle any size string that gets returned. Here’s an example that uses a pathname to open a resource file.

;5

(with-pstrs ((file-name “hd:MACL:foo.rsrc”)) (setf refnum(_OpenResFile 
:ptr file-name :word)))

The variables you define are bound to pointers to Pascal strings which are initialized to the value of the LISP string you provide. For functions that return strings, you can create a LISP string from the Pascal string using %get-string.

rlet/rref/rset - These forms let you allocate, reference, and initialize records. You’ll need to (require ‘records) to load in records.Lisp which contains record definitions. MACLs handling of Pascal records (even variants) is pretty nice. Here is an example using a rectangle:

;6

(rlet ((r :rect  :top 0 :left 0 :bottom 20 :right 50))   (format t “top=~s,left=~s~%” 
(rref r :rect.top) (rref r :rect.left));check vals (_Pt2Rect :long #@(10 
10) :long #@(50 50) :ptr r)  ;change rect (format t “top=~s,left=~s~%” 
(rref r :rect.top) (rref r :rect.left)) ;check vals (rset r :rect.top 
-90) ;change it again (format t  “top=~s,left=~s~%” (rref r :rect.top) 
(rref r :rect.left)) ;check vals)

To conserve space I’ll defer further elaboration on these to the MACL manual which does a pretty good job. You’ll end up using rlet, rref, and rset a lot, so it’s worth taking some time to learn them. Since the record definitions give MACL detail on the field structure, messed up field names get caught. making these calls reasonably foolproof.

%stack-block - This is the catch all. You specify the size you need and it allocates raw chunks of memory on the stack. Initialization is left for you to do. A whole variety of functions like %get-word, %put-word, %get-ptr, are provide for setting and accessing.memory. Here is an example call to GetResInfo. Three of the parameters are var, so we have to allocate some space for them and pass in the pointers (and yes, I could have used with-returned-pstrs for the rsrcName). Presumably, theResource, has been set to the handle of some resource by some earlier call to GetResource. Once the trap call is returned, we extract the return values using %get-???. The pointers all become invalid once the %stack-block exits, so if we want to save the return values, we have to store their values in some LISP variables.

;7

(%stack-block (  (rsrcID 2) (rsrcType 4)(rsrcName 256)) (_GetResInfo
 :ptr theResource :ptr rsrcID :ptr rsrcType :ptr rsrcName)(setf the-id 
(%get-word rsrcID))(setf the-type (%get-ostype rsrcType))(setf the-name 
(%get-string rsrcName)))

These are the most general purpose, read dangerous, of the memory allocation/access functions. The real programmers out there might have noticed that by using field offsets this facility can can supplant the aforementioned record accessing functions. I strongly recommend against this type of thinking. For the most part, if you use record definitions you can avoid %stack-block and %get-??? and be much better off. Occasionally, they’re unavoidable. Most commonly, when you need to deal with integer or longint var parameters.

In summary, when you pass records, strings or var parameters you should allocate storage using either with-pstrs, rlet, or %stack-block, and pass in pointers to the storage. For var parameters, remember to access the returned values via one of the %get-??? functions. If you need to keep the returned values around, setf some LISP variable to the value.

Of course there are other ways to allocate/deallocate memory. There’s the NewPtr and NewHandle ToolBox calls and MACL provides make-record. The disadvantage to using these calls is that the memory you allocate is permanent, read clutters the heap, until you remember to deallocate it. But, one in a while, you need the memory you allocate to stick around a while.

Defining Pascal Record Types in LISP

When using the ToolBox another file you commonly need is records.Lisp. As with traps.Lisp, this is best accomplished by putting (require ‘records) in your code. What records.Lisp does is define various record types used by the ToolBox so that you can use them with rlet,rref, rset, and the like. Many of the common types are defined in records.Lisp, but. there are many omissions. Deficiencies can be corrected by defining additional record types using the MACL’s defrecord mechanism

To use the sound manager I had to define the Sound Manager types, SndCommand and SndChannel. Below is the definition for SndCommand.

;8

  (defrecord (SndCommand :pointer)    (cmd :integer)    (param1 :integer) 
   (param2 :longint)    )

The type after the record name, in this case :pointer, is the default storage used by rlet or rref when allocating or accessing records of this type. The choices are :pointer or:handle. The rest of the definition is just field name - field type pairs. Just to make things interesting, the types used in record definitions are different than the types used in trap calls. The choices are: :boolean, :byte, :character, :handle, :integer, :longint, :ostype, :point, and:pointer. More types were actually necessary because the four types used for trap call arguments are not specific enough for purposes of defining records. For instance, when defining a record you may need to specify a one byte :boolean field, as opposed to passing a character as an argument, when you can just use a :word (a minimum of two bytes is pushed on the stack, the extra byte is just wasted). I’m not sure why they don’t simplify things and just use the record field types for trap calls.

The defrecord mechanism also allows for variant records. The most notable use is in defining the type Rect, which can be accessed through the :top, :left, :bottom, and :right fields or through the :topleft and :bottomright fields (and yes, it should be :botright, it’s an error in records.Lisp)

Using the Sound Manager

Low Level Routines

I consider the five routines; get-snd, snd-open-channel, snd-close-channel, snd-command, and snd-command-immediate low level in that they require knowledge of the sound manager to use safely. They are not exported from sndMgr.Lisp and are not intended for use by the general MACL user.

get-snd: To play a sound, the first thing you need is a handle to the sound resource. get-snd provides a nice way to do this. It takes advantage of LISP’s weak typing to accept either a resource id or a resource name.and calls either GetResource or GetNamedResource as appropriate.

snd-open-channel: Since we want to play the sound asynchronously, we need to pass a SndChannelPtr to SndPlay. So we need to allocate a SndChannel using SndNewChannel (traps.Lisp has the trap name misspelled as _SndNewChan) By passing nil for the chan parameter, we get the convenience of having the SoundManager allocate storage. for the channel (SndDisposeChannel will free this storage) It is important to note that the chan is a var parameter, requiring us to allocate storage for it and pass its address. Also note that it’s initialized to nil using %put-ptr. This is a bit unusual as var parameters generally just pass information out, requiring no initialization.

The SndChannelPtr returned by SndNewChannel is stored in the global variable *snd-channel-p*. I rationalize this use of a global variable in two ways. It’s necessary to keep the around the address of the SndChannel so we can later dispose of it. Furthermore, by making sure *snd-channel-p* gets set back to nil when we close the channel, it serves as a flag indicating, by a non-nil value, that we’ve got a open sound channel. This is how the first line of snd-open-channel, (when *snd-channel_p* (snd-close-channel)), is able to protect the careless programmer who leaves an open SndChannel lying around.

The careful reader will note that there is more going here, the call to _NewPtr and _StuffHex. This has to do with the sound channel’s call back procedure, which is used to detect when the sound is done playing. I’ll defer further elaboration to the discussion of snd-open and snd-p.

snd-close-channel: Simply calls SndDisposeChannel to get rid of the sound channel, sets *snd-channel-p*, and frees up the storage used by the channel’s call back procedure.

snd-command: Provides a convenient way to queue up a command in the currently opened SndChannel, like execute your call back procedure.

snd-command-immediate: Provides a convenient way to issue a command for the currently opened SndChannel to execute immediately, like shutup.

High Level Routines

snd-open: Gets the specified sound resource, opens a sound channel, and plays the sound, asynchronously.by default. It also set the userInfo field of the channel to -1 to indicate that the sound is currently playing and then calls snd-command to queue up a callBackCmd command to be executed when the playing is over. The callBackCmd will, in turn, cause the channels call back procedure to be called which will set userInfo to 0 indicating the sound is done playing.

snd-close: It’s important to balance every call to snd-open with a call to snd-close as soon as possible after the sound plays. While you hold an open SndChannel no others can be opened. Yes, the next time you call snd-open the previous SndChannel will get closed, but in the mean time other applications are stuck, plus you won’t get system beeps. It would be nice if a SndChannel’s call back routine could close it for us, but the sound manager documentation specifically mention this is not allowed.

snd-halt: Simply sends immediate commands to quiet and flush the current SndChannel and then close it.

snd-p: This function returns whether or not a sound is still playing. Unfortunately, the sound manager doesn’t provide any calls to do this for us. We accomplish this using the userInfo field of the channel as a flag. So all snd-p has to do is examine this field.

The channel’s call back procedure is in charge of setting this flag to zero when the sound is done playing. But nothing is ever that easy. Call back procedures are called at interrupt time and thus have some strict limitations. First off, whenever you pass a pointer to the ToolBox, it expects a pointer to a Pascal function. So you can’t expect to use a regular LISP function. MACL, does provide the special form, defpascal, to let you write a LISP function with a Pascal style interface. However, it doesn’t seem to create functions strict enough to be called at interrupt time. My attempts at using it to define the call back procedure would often crash the system.

So, the solution. Write it in another language. I wrote it as a CODE resource in THINK C. It was a one line function, compiled to only 58 bytes. Since it was so small, I figured the easiest way to use it from MACL was to allocate 58 bytes of memory and just stuff the compiled machine code right into.it. So using ResEdit I copied the hex digits that comprised the CODE resource and then brought them into sndMgr.Lisp where they’re stored in the LISP string, *snd-call-back-mcode*.

Whenever a sound channel is created, 58 bytes are allocated with NewPtr, and then StuffHex is used to install the machine code of the compiled call back procedure. Sounds ugly, doesn’t it? But it worked first time I tried it, honest.

You might be asking, what if the call back procedure needed to be a big complicated procedure. Well, we could have used a resource file to hold the CODE resource and then used a derefenced handle to the resource. But this would have made sndMgr.Lisp trickier to use. Users would have to make sure to have a resource file around and open before playing a sound.

Wrapping Up

Attached is the source to sndMgr.Lisp. To try out the code first load sndMgr.Lisp and then play around with the test code in the comment at the end of the file. It would be pretty dull to include the hex source to a ‘snd ‘ resource, so your on your own to get a more interesting sound to play. The test code shows you how to open the resource file, once you get it. Use ResEdit to find out the resource id’s of the sounds it contains.

If the formatting of the LISP source looks a bit funny to you, it’s because of the 3.5" column width of MacTutor. Sorry If it makes reading it difficult.

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; sndMgr.Lisp
;;
;; Copyright © 1990 Michael S. Engber
;; All Rights Reserved
;;
;; Sound Manager access from LISP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(require ‘traps)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Sound Manager definitions (missing from Records.Lisp)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(eval-when (compile load eval)
  
  (defrecord (SndCommand :pointer)
    (cmd :integer)
    (param1 :integer)
    (param2 :longint)
    )
  
  (defrecord (SndChannel :pointer)
    (nextChan :pointer)
    (firstMode :pointer)
    (callBack :pointer)
    (userInfo :longint)
    (wait :longint) ;Time
    (cmdInProgress SndCommand)
    (flags :integer)
    (qLength :integer)
    (qHead :integer)
    (qTail :integer)
    (queue :longint) ;array [0..stdQLength-1] of SndCommand
    )
  
  ;;; sound commands
  (defconstant $nullCmd 0)
  (defconstant $initCmd 1)
  (defconstant $freeCmd 2)
  (defconstant $quietCmd 3)
  (defconstant $flushCmd 4)
  (defconstant $waitCmd 10)
  (defconstant $pauseCmd 11)
  (defconstant $resumeCmd 12)
  (defconstant $callBackCmd 13)
  (defconstant $syncCmd 14)
  (defconstant $emptyCmd 15)
  (defconstant $tickleCmd 20)
  (defconstant $requestNextCmd 21)
  (defconstant $howOftenCmd 22)
  (defconstant $wakeUpCmd 23)
  (defconstant $availableCmd 24)
  (defconstant $versionCmd 25)
  (defconstant $scaleCmd 30)
  (defconstant $tempoCmd 31)
  (defconstant $noteCmd 40)
  (defconstant $restCmd 41)
  (defconstant $freqCmd 42)
  (defconstant $ampCmd 43)
  (defconstant $timbreCmd 44)
  (defconstant $waveTableCmd 60)
  (defconstant $phaseCmd 61)
  (defconstant $soundCmd 80)
  (defconstant $bufferCmd 81)
  (defconstant $rateCmd 82)
  (defconstant $continueCmd 83)
  (defconstant $midiDataCmd 100)
  
)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar *snd-channel_p* nil “pointer to currently opened sound channel”)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defmacro with-sound (sndSpec &rest forms)
  “(sndSpec) -forms-
Protective ‘with’ wrapper for using sounds.”
  (unless (listp sndSpec)
    (error “bad options”))
  ‘(unwind-protect (progn (snd-open ,(first sndSpec)) ,@forms) (snd-close)))

(defun snd-halt ()
  “void
Halts any sound in progress & closes the channel.”
  (when *snd-channel_p*
    (snd-command-immediate $quietCmd 0 0)
    (snd-command-immediate $flushCmd 0 0)
    (snd-close)))

(defun snd-p ()
  “void
Returns whether a sound (played with snd-open) is currently playing.”
  (when *snd-channel_p*
    (null (zerop (rref *snd-channel_p*
                    :SndChannel.userInfo)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;snd-open & snd-close open a sound channel,
;;play a sound, and then close  the sound
;;channel. Since only one sound channel can
;;be active at any time,  it is important
;;that every call to snd-open be followed by
;;a call to  snd-close (or snd-halt) as soon
;;as possible. While a sound channel is open,
;;no other sounds (like system beeps) can
;;play.
;;
;; The with-sound macro safely takes care of
;;all this for you. When control leaves the
;;body, either normally or abnormally, the
;;sound channel is closed.

(defun snd-open (sndSpec &key (async t))
  “sndSpec &key (async t)
Plays the specified sound (asynchronously by
default) sndSpec is either a resource number
or name of a ‘snd ‘ resource.”
  (let ((snd_h (get-snd sndSpec)))
    (when snd_h
      (cond
       (async
        (snd-open-channel)
        (rset *snd-channel_p*
              :SndChannel.userInfo -1)
        (_SndPlay :ptr *snd-channel_p*
                  :ptr snd_h
                  :word -1
                  :word)
        (snd-command $callBackCmd 0 0))
       (t
        (snd-close)
        (_SndPlay :ptr nil
                  :ptr snd_h
                  :word 0 :word))))))

(defun snd-close ()
  “void
Cleans up after sound finishes.”
  (snd-close-channel))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;Determining whether a sound is still
;;playing (snd-p) is done using a  Sound
;;Manager call back routines. Before playing
;;a sound, the userInfo  field of the sound
;;channel is set to -1. When the sound
;;completes, the  call back routine is
;;called and it sets userInfo to zero. snd-p
;;simply  checks the value of userInfo.

;;Since the call back routine is called at
;;interrupt time, there are several
;;restrictions on it (see Sound Manager
;;chapter of IM) which MACL’s defpascal
;;mechanism does not obey. So it was written
;;in C. The compiled code is small enough
;;that we can just copy its machine code into
;;memory when a sound channel is created
;;(avoiding loading CODE resources or
;;external function calls)
;;
;;   #include <SoundMgr.h>
;;
;;   pascal void main (SndChannelPtr theChan,
                       SndCommand* theCmd){
;;    theChan->userInfo = 0L;
;;   }
;;
;;

(defvar *snd-call-back-mcode* “600E0000434F444501F400000000000041FAFFEE4E714E71600000024E560000206E000C42A8000C4E5E205F4FEF00084ED04D41494E20202020”
  “machine code (hex) for call back routine”)


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun get-snd (sndSpec)
  “sndSpec
Returns a handle to the specified ‘snd ‘ resource. sndSpec is either 
a resource number or name of a ‘snd ‘ resource.”
  (typecase sndSpec
   (fixnum (_GetResource :ostype “snd “
                         :word sndSpec
                         :ptr))
   (string (with-pstrs ((name sndSpec))
            (_GetNamedResource :ostype “snd “
                               :ptr name
                               :ptr)))
   (otherwise
     (error “bad resource specification [~S]”
             sndSpec))))

(defun snd-open-channel ()
  “void
Opens a new channel for sound play.”
  (when *snd-channel_p* (snd-close-channel))
  (%stack-block ((channel_p 4))
    
    ;; pass nil for the channel_p so the Sound Mangager will allocate 
space
    (%put-ptr channel_p nil)
    
    ;; stuff machine code for call back routine into memory
    (let ((call-back-ptr
           (_NewPtr  :d0 (/ (length *snd-call-back-mcode*) 2)
                    :a0)))
      (with-pstrs ((p *snd-call-back-mcode*))
        (_StuffHex :ptr call-back-ptr
                   :ptr p))
    
    (if (zerop
          (_SndNewChanne :ptr channel_p
                         :word 0
                         :long 0
                         :ptr call-back-ptr
                         :word))
      (setf *snd-channel_p*
            (%get-ptr channel_p))
      (error “allocating sound channel.”)))))

(defun snd-close-channel ()
  (when *snd-channel_p*
    (_DisposPtr :a0 (rref
                      *snd-channel_p*
                      :SndChannel.callBack)
                :d0)
    (_SndDisposeChannel :ptr *snd-channel_p*
                        :word 0
                        :word)
    (setf *snd-channel_p* nil)))

(defun snd-command (cmd param1 param2)
  “cmd  param1 param2
Adds the specified command to the sound channel’s queue.”
  (when *snd-channel_p*
    (rlet ((cmd_p :SndCommand
                  :cmd cmd
                  :param1 param1
                  :param2 param2))
      (_SndDoCommand :ptr *snd-channel_p*
                     :ptr cmd_p
                     :word 0
                     :word))))

(defun snd-command-immediate (cmd param1 param2)
  “cmd param1 param2
Sends the sound channel the specified command to immediately execute.”
  (when *snd-channel_p*
    (rlet ((cmd_p :SndCommand
                  :cmd cmd
                  :param1 param1
                  :param2 param2))
      (_SndDoImmediat :ptr *snd-channel_p*
                      :ptr cmd_p
                      :word))))

#|

test code

This plays a sound asychronously. During play it checks to see if the shift key is pressed - if so it halts the sound immediatlely.It uses the ‘snd ‘ resource id = 1, the standard system beep.

;10

(with-sound (1)
    (loop (when (or
                  (shift-key-p)
                  (null (snd-p)))
            (snd-halt) (return))))

The standard system beep is so short that the above code isn’t too exciting as is. You may want to try some of the longer system beeps like Clink-Klang (id = 2) if you have them installed. Or better yet, open a sound resource file of your own with this code.

;11

(with-pstrs ((res_file “your sound file”))
  (_openresfile :ptr res_file :word))
|#

 

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Software Updates via MacUpdate

NetShade 6.3.1 - Browse privately using...
NetShade is an anonymous proxy and VPN app+service for Mac. Unblock your Internet through NetShade's high-speed proxy and VPN servers spanning seven countries. NetShade masks your IP address as you... Read more
Dragon Dictate 4.0.7 - Premium voice-rec...
With Dragon Dictate speech recognition software, you can use your voice to create and edit text or interact with your favorite Mac applications. Far more than just speech-to-text, Dragon Dictate lets... Read more
Persecond 1.0.2 - Timelapse video made e...
Persecond is the easy, fun way to create a beautiful timelapse video. Import an image sequence from any camera, trim the length of your video, adjust the speed and playback direction, and you’re done... Read more
GIMP 2.8.14p2 - Powerful, free image edi...
GIMP is a multi-platform photo manipulation tool. GIMP is an acronym for GNU Image Manipulation Program. The GIMP is suitable for a variety of image manipulation tasks, including photo retouching,... Read more
Sandvox 2.10.2 - Easily build eye-catchi...
Sandvox is for Mac users who want to create a professional looking website quickly and easily. With Sandvox, you don't need to be a Web genius to build a stylish, feature-rich, standards-compliant... Read more
LibreOffice 5.0.1.2 - Free, open-source...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
f.lux 36.1 - Adjusts the color of your d...
f.lux makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day. Ever notice how people texting at night have that eerie blue glow? Or wake... Read more
VirtualBox 5.0.2 - x86 virtualization so...
VirtualBox is a family of powerful x86 virtualization products for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers... Read more
File Juicer 4.43 - Extract images, video...
File Juicer is a drag-and-drop can opener and data archaeologist. Its specialty is to find and extract images, video, audio, or text from files which are hard to open in other ways. In computer... Read more
Apple MainStage 3.2 - Live performance t...
MainStage 3 makes it easy to bring to the stage all the same instruments and effects that you love in your recording. Everything from the Sound Library and Smart Controls you're familiar with from... Read more

ReBoard: Revolutionary Keyboard (Utilit...
ReBoard: Revolutionary Keyboard 1.0 Device: iOS Universal Category: Utilities Price: $1.99, Version: 1.0 (iTunes) Description: Do everything within the keyboard without switching apps! If you are in WhatsApp, how do you schedule a... | Read more »
Tiny Empire (Games)
Tiny Empire 1.1.3 Device: iOS Universal Category: Games Price: $2.99, Version: 1.1.3 (iTunes) Description: Launch cannonballs and blow tiny orcs into thousands of pieces in this intuitive fantasy-themed puzzle shooter! Embark on an... | Read more »
Astropad Mini (Productivity)
Astropad Mini 1.0 Device: iOS iPhone Category: Productivity Price: $4.99, Version: 1.0 (iTunes) Description: *** 50% off introductory price! ​*** Get the high-end experience of a Wacom tablet at a fraction of the price with Astropad... | Read more »
Emo Chorus (Music)
Emo Chorus 1.0.0 Device: iOS Universal Category: Music Price: $1.99, Version: 1.0.0 (iTunes) Description: Realistic Choir simulator ranging from simple Chorus emulation to full ensemble Choir with 128 members. ### introductory offer... | Read more »
Forest Spirit (Games)
Forest Spirit 1.0.5 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.5 (iTunes) Description: | Read more »
Ski Safari 2 (Games)
Ski Safari 2 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: The world's most fantastical, fun, family-friendly skiing game is back and better than ever! Play as Sven's sister Evana, share... | Read more »
Lara Croft GO (Games)
Lara Croft GO 1.0.47768 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.47768 (iTunes) Description: Lara Croft GO is a turn based puzzle-adventure set in a long-forgotten world. Explore the ruins of an ancient... | Read more »
Whispering Willows (Games)
Whispering Willows 1.23 Device: iOS Universal Category: Games Price: $4.99, Version: 1.23 (iTunes) Description: **LAUNCH SALE 50% OFF** - Whispering Willows is on sale for 50% off ($4.99) until September 9th. | Read more »
Calvino Noir (Games)
Calvino Noir 1.1 Device: iOS iPhone Category: Games Price: $3.99, Version: 1.1 (iTunes) Description: The film noir stealth game. Calvino Noir is the exploratory, sneaking adventure through the 1930s European criminal underworld.... | Read more »
Angel Sword (Games)
Angel Sword 1.0 Device: iOS Universal Category: Games Price: $6.99, Version: 1.0 (iTunes) Description: Prepare to adventure in the most epic full scale multiplayer 3D RPG for mobile! Experience amazing detailed graphics in full HD.... | Read more »

Price Scanner via MacPrices.net

Big Grips Lift Handle For iPad Air and iPad A...
KEM Ventures, Inc. which pioneered the extra-large, super-protective iPad case market with the introduction of Big Grips Frame and Stand in 2011, is launching Big Grips Lift featuring a new super-... Read more
Samsung Launches Galaxy Tab S2, Its Most Powe...
Samsung Electronics America, Inc. has announced the U.S. release of the Galaxy Tab S2, its thinnest, lightest, ultra-fast tablet. Blending form and function, elegant design and multitasking power,... Read more
Tablet Screen Sizes Expanding as iPad Pro App...
Larger screen sizes are gaining favor as the tablet transforms into a productivity device, with shipments growing 185 percent year-over-year in 2015. According to a new Strategy Analytics’ Tablet... Read more
Today Only: Save US$50 on Adobe Elements 13;...
Keep the memories. lose the distractions. Summer’s winding down and it’s time to turn almost perfect shots into picture perfect memories with Elements 13. And get the power to edit both photos and... Read more
1.4GHz Mac mini on sale for $449, save $50
Best Buy has the 1.4GHz Mac mini on sale for $50 off MSRP on their online store. Choose free shipping or free local store pickup (if available). Price for online orders only, in-store price may vary... Read more
12-inch 1.1GHz Gold MacBook on sale for $1149...
B&H Photo has the 12″ 1.1GHz Gold Retina MacBook on sale for $1149.99 including free shipping plus NY sales tax only. Their price is $150 off MSRP, and it’s the lowest price available for this... Read more
27-inch 3.3GHz 5K iMac on sale for $1849, sav...
Best Buy has the 27″ 3.3GHz 5K iMac on sale for $1849.99. Their price is $150 off MSRP, and it’s the lowest price available for this model. Choose free shipping or free local store pickup (if... Read more
Worldwide Tablet Shipments Expected to Declin...
Does Apple badly need a touchscreen convertible/hybrid laptop MacBook? Yes, judging from a new market forecast from the International Data Corporation (IDC) Worldwide Quarterly Tablet Tracker, which... Read more
Continued PC Shipment Shrinkage Expected Thro...
Worldwide PC shipments are expected to fall by -8.7 percent in 2015 and not stabilize until 2017, according to the latest International Data Corporation (IDC) Worldwide Quarterly PC Tracker data. The... Read more
Imminent iPhone 6s Announcement Leads To 103%...
NextWorth Solutions, with its online and in-store electronics trade-in programs including http://NextWorth.com, reports that it has experienced a 103 percent surge in quoted trade-in values over the... Read more

Jobs Board

*Apple* Retail Online Store: Customer Insigh...
**Job Summary** Apple Retail (Online Store) is seeking an experienced e-commerce analytics professional to join the Customer Insights Team. The Web e-Commerce Analyst Read more
*Apple* Music, Business Operations - Apple I...
Changing the world is all in a day039s work at Apple . If you love innovation, here039s your chance to make a career of it. You039ll work hard. But the job comes with Read more
WW *Apple* Retail Online Store: Customer In...
**Job Summary** The Apple Retail - Online Store is seeking an experienced web merchandising analytics professional to join the Customer Insights Team. The Web Read more
Senior Payments Security Manager - *Apple*...
**Job Summary** Apple , Inc. is looking for a highly motivated, innovative and hands-on senior payments security manager to join the Apple Pay security team. You will Read more
Software QA Engineer, *Apple* Pay Security...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
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