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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

iClock Pro 3.8 - Customize your menubar...
iClock Pro is a menu-bar replacement for Apple's default clock. iClock Pro is an update, total rewrite, and improvement to the popular iClock. Have the day, date, and time in different fonts and... Read more
VirtualBox 5.2.0 - 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
Dropbox 37.4.29 - Cloud backup and synch...
Dropbox is an application that creates a special Finder folder that automatically syncs online and between your computers. It allows you to both backup files and keep them up-to-date between systems... Read more
Google Chrome 62.0.3202.62 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
Chromium 62.0.3202.62 - Fast and stable...
Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all Internet users to experience the web. Version 62.0.3202.62: High CVE-2017-5124: UXSS with... Read more
Fantastical 2.4.3 - Create calendar even...
Fantastical 2 is the Mac calendar you'll actually enjoy using. Creating an event with Fantastical is quick, easy, and fun: Open Fantastical with a single click or keystroke Type in your event... Read more
Things 3.2.1 - Elegant personal task man...
Things is a task management solution that helps to organize your tasks in an elegant and intuitive way. Things combines powerful features with simplicity through the use of tags and its intelligent... Read more
A Better Finder Attributes 6.06 - Change...
A Better Finder Attributes is the ultimate file-tweaking tool for OS X. It combines photo-shooting date and file date changing along with a few unique tricks of its own. Change EXIF Timestamps at... Read more
MacCleanse 6.0.5 - $29.95
MacCleanse is the product of thousands of hours of intense research and development. It meticulously scans all of the nooks and crannies of a computer for unnecessary junk that can take up huge... Read more
Smultron 10.0.2 - Easy-to-use, powerful...
Smultron 10 is an elegant and powerful text editor that is easy to use. You can use Smultron 10 to create or edit any text document. Everything from a web page, a note or a script to any single piece... Read more

4 of the best Halloween updates for mobi...
Halloween is certainly one of our favorite times for mobile game updates. Many popular titles celebrate this spooky season with fun festivities that can stretch from one week to even the whole month. As we draw closer and closer to Halloween, we'... | Read more »
Fire Rides guide - how to swing to succe...
It's another day, which means another Voodoo game has come to glue our hands to our mobile phones. Yes, it's been an especially prolific month for this particular mobile publisher, but we're certainly not complaining. Fire Rides is yet another... | Read more »
Time Recoil (Games)
Time Recoil 1.0.1 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0.1 (iTunes) Description: Time Recoil is a top-down shooter where you kill to slow time, dominate slow motion gunfights, and trigger devastating special... | Read more »
Campfire Cooking (Games)
Campfire Cooking 1.0 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: | Read more »
Returner 77 (Games)
Returner 77 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Returner 77 is a cinematic space mystery puzzle game. You are in a giant alien spaceship hovering above Earth, after everything... | Read more »
Dune! guide - how to toe the line and ge...
Publisher Voodoo is at it again with an all new high score chaser -- Dune! In this fast-paced arcade game, you have to propel yourself along sand dunes, gaining enough momentum to jump above the line to score points, while making sure you have... | Read more »
The best deals on the App Store this wee...
Happy Tuesday, dear readers. Your favorite part of the week as officially arrived. It's time to take a look at the best deals in games. Things are admittedly a bit sparse, but there are a few diamonds in the rough to see you through if you're... | Read more »
Be the last person standing in Legacy of...
Yoozoo Games’ popular action MMO Legacy of Discord is getting a huge new update to celebrate its first anniversary. Perhaps the biggest change is the addition of an exciting survival mode titled Last Guardian. This new survival mode will pit you... | Read more »
Home Street guide - how to make friends...
From the creators of Food Street comes Home Street, a new simulation game that tasks you with building a social network and designing a beautiful home. It's a bit like The Sims, but you won't have to worry about the daily chores involved (feeding,... | Read more »
Color Ballz guide - how to bounce to the...
Color Ballz is an addictive new arcade title from Ketchapp Studios. It takes old school mechanics from games like Brickles and puts a fun twist on it. Your job? To catch balls with a paddle and send them back into a chute to be carried back to... | Read more »

Price Scanner via MacPrices.net

13″ MacBook Pros on sale for up to $120 off M...
B&H Photo has 2017 13″ MacBook Pros in stock today and on sale for up to $120 off MSRP, each including free shipping plus NY & NJ sales tax only: – 13-inch 2.3GHz/128GB Space Gray MacBook... Read more
15″ MacBook Pros on sale for up to $200 off M...
B&H Photo has 15″ MacBook Pros on sale for up to $200 off MSRP. Shipping is free, and B&H charges sales tax in NY & NJ only: – 15″ 2.8GHz MacBook Pro Space Gray (MPTR2LL/A): $2249, $150... Read more
Roundup of Apple Certified Refurbished iMacs,...
Apple has a full line of Certified Refurbished 2017 21″ and 27″ iMacs available starting at $1019 and ranging up to $350 off original MSRP. Apple’s one-year warranty is standard, and shipping is free... Read more
Sale! 27″ 3.8GHz 5K iMac for $2098, save $201...
Amazon has the 27″ 3.8GHz 5K iMac (MNED2LL/A) on sale today for $2098 including free shipping. Their price is $201 off MSRP, and it’s the lowest price available for this model (Apple’s $1949... Read more
Sale! 10″ Apple WiFi iPad Pros for up to $100...
B&H Photo has 10.5″ WiFi iPad Pros in stock today and on sale for $50-$100 off MSRP. Each iPad includes free shipping, and B&H charges sales tax in NY & NJ only: – 10.5″ 64GB iPad Pro: $... Read more
Apple iMacs on sale for up to $130 off MSRP w...
B&H Photo has 21-inch and 27-inch iMacs in stock and on sale for up to $130 off MSRP including free shipping. B&H charges sales tax in NY & NJ only: – 27″ 3.8GHz iMac (MNED2LL/A): $2179 $... Read more
2017 3.5GHz 6-Core Mac Pro on sale for $2799,...
B&H Photo has the 2017 3.5GHz 6-Core Mac Pro (MD878LL/A) on sale today for $2799 including free shipping plus NY & NJ sales tax only . Their price is $200 off MSRP. Read more
12″ 1.2GHz Space Gray MacBook on sale for $11...
Amazon has the 2017 12″ 1.2GHz Space Gray Retina MacBook on sale for $100 off MSRP. Shipping is free: 12″ 1.2GHz Space Gray MacBook: $1199.99 $100 off MSRP Read more
Bare Bones Software Releases macOS High Sierr...
Bare Bones Software has announced the release and immediate availability of BBEdit 12.0, a significant upgrade to its professional strength text and code editor. BBEdit 12 introduces a new foundation... Read more
Yale Announces Availability of Apple HomeKit-...
Yale Locks & Hardware has announced that Apple HomeKit support for its Assure Lock family is available this month. The new Yale iM1 Network Module, which provides support for the Apple Home app... Read more

Jobs Board

*Apple* News Product Marketing Mgr., Publish...
Job Summary The Apple News Product Marketing Manager will work closely with a cross-functional group to assist in defining and marketing new features and services. Read more
Fraud Analyst, *Apple* Advertising Platform...
Job Summary Apple Ad Platforms has an opportunity to redefine advertising on mobile devices. Apple reaches hundreds of millions of iPhone, iPod touch, and iPad Read more
*Apple* Information Security - Security Data...
Job Summary This role is responsible for helping to strengthen Apple 's information security posture through the identification and curation of security event data. Read more
Lead *Apple* Solution Consultant - Apple In...
…develop a team of diverse partner employees focusing on excellence to deliver the Apple story. Even when you're not present, you will maintain a consistent influence Read more
watchOS Frameworks Engineering Manager, *App...
Job Summary Join the team that is shaping the future of software development for Apple Watch! Apple is looking for an exceptional software engineering leader to Read more
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