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XCMD in Think C
Volume Number:5
Issue Number:5
Column Tag:HyperChat™

XCMD Corner: XCMDs in Think C

By Donald Koscheka, Arthur Young & Company, MacTutor Contributing Editor

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Exploring XCMDs using just one development system is a lot like learning to play music on just one instrument. This is unfortunate because the Macintosh offers a virtual orchestra of development systems. As in learning to play a second instrument, learning a new development system often boils down to nothing more than learning how to transcribe the music.

Your programming environment is your instrument (writing a program is more like writing a piece of music than playing it). If you happen to own a copy of MPW you have no trouble using the code in this column because it’s all written for MPW. If you use a different development system , you’ll need to transcribe my listings to play on your particular development system.

In the past, I’ve been terribly guilty of catering to the MPW clique. My reasons were perhaps not so subtle: I use MPW at work; I’m comfortable with it, and I know that it directly supports an interface to XCMDs. After purchasing a copy of MPW 3.0, I realized that I might be making a mistake. For starters, MPW requires an expensive and time consuming learning curve; perhaps not everyone wants to spend several hundred dollars for sophistication they may never need.

Other development systems offer features that are not available in MPW such as a high quality source level debugger. Unfortunately several development systems lack key capabilities like support for XCMDs. Although you might expect LightspeedC to support XCMDs out of the box, it doesn’t. I’m not sure I understand the reason, but it doesn’t matter. Adding XCMD support to any compiler should be a very simple job.

Afterall, an XCMD is just another type of resource. If LightspeedC can create specialized resources such as window definitions and drivers, it already contains some of the support we need.

• Setting up the project

As luck, or design foresight, would have it, LightspeedC supports a generalized resource type called the “CODE” Resource. CODE resource projects are created like any other project in LightspeedC with the exception that you specify the project as a code resource in the set project type dialogue (see figure 1). You specify most of the information that the resource manger wants in this dialogue.

The custom header option requires a little elaboration. The standard interface to code resources branches to the entry point: main() . Selecting the Custom header option causes the entry point to be the first function in the file in which your main() is defined. XCMDs follow the second course as a matter of style.

Set the resource type to ‘XCMD’ or ‘XFCN’ according to the type of Hypercard interface you want.

Figure 1. Setting up a Code Resource using the Set Project Type Dialogue

• Writing the XCMD

In LightspeedC, a code resource has the same form as a “C” program. You define the entry point as:

 pascal void main( paramPtr ) 

ParamPtr is a pointer to a HyperTalk XCMDBlock. From there, your code looks like a vanilla “C” application. The same restrictions apply as on all CODE resources: no globals or statically initialized strings. CODE resources, of any kind, have no knowledge of globals at build time because they can’t make any assumptions about which application will load them! Strings suffer the same fate - “C” allocates statically defined strings in the application’s global pool. You’re not building an application so you don’t have a global pool - you must either define strings the hard way or load them in from the resource fork.

Listing 1 is a simple XCMD that returns the string “Hello World” to Hypercard. While the code itself is wholly unimaginative, it does demonstrate that the interface to Hypercard and the callback mechanism work satisfactorily. Anyhow there’s a time for imagination and a time to just get things done. Porting an interface falls to the latter category.

Include the header file, “HyperXCMD.h” (listing 2 ) in your code. This is the standard interface to Hypercard transposed for LightspeedC. There aren’t a lot of differences between the two as should be the case. Nonetheless this exercise proves quite useful in scoping out the idioms of a particular language implementation.

• The Hypercard “Glue”

You need to create a project which at the least includes MacTraps, your XCMD code and a special file called “XCMDGlue.c” (Listing 3) which interfaces (or glues) your XCMD to Hypertalk’s callback mechanism. I took the liberty of translating XCMDGlue.in.c from MPW “C” to LightspeedC. The major difference between the MPW and Think versions of the glue is that I use the CallPascal function available in LightspeedC to jump to the subroutine pointed to by paramPtr->entryPoint. Pascal routines push parameters from left to right and the subroutine is responsible for clearing the stack parameters. “C” pushes from right to left and the caller clears the stack.

We know that the callback engine uses the Pascal calling sequence because the parameters aren’t left on the stack after the call. Whether we push from right to left or left to right isn’t relevant here for an obvious reason that’s left as an exercise to the reader.

Add XCMDGlue.c to the project rather than including it at the end of the XCMDS source code as is the case with MPW. I like this feature of Think “C” - you keep track of the source modules at the project level and not at the source code level.

• Creating the resource

Once all modules compile,use the “Create Code Resource” menu option to create the code resource. LightspeedC presents a dialogue asking for the name of an output file. Enter the name of a file but not your output stack: LightspeedC completely erases the previous contents of both forks of the output file before writing out the code resource!

Select the “smart link” option when creating a code resource. Your links will be slower, but your XCMDs will be quite a bit smaller (The example in listing 3 compiles to 12.5K with smart link of and 2.5K with smart link on). Of course, you can speed up turnaround during development by leaving this option unselected.

That’s it! Use ResEdit or Rescopy to copy the XCMD into your stack. Perhaps LightspeedC will release a future version of “C” that will build code resources directly into the target file (if you try this now, the entire contents of the target file will be lost). In the meantime, the extra step needed to copy the resource into your stack is a small price to pay for an outstanding development system.

I hope the information in this article will help those of you who need to create an XCMD interface for another development system. The process is really rather simple and it provides you one of those rare opportunities in programming where you can get a lot done without doing a lot of work!

Listing 1:

/********************************/
/* File: SimpleXCMD.c*/
/* */
/* This is what a simple XCMD */
/* written in Lightspeed “C”*/
/* In order to build this code*/
/* resource, you will need the*/
/* two files “HyperXCMD.h” and*/
/* XCMDGlue.c.   */
/* */
/* ----------------------------  */
/* To Build:*/
/* */
/* (1) Create a project using */
/* this file as well as the */
/* XCMD.Glue.c file. (Set */
/* project type to XCMD (or */
/* XFCN) from the Project menu.  */
/* */
/* (2) Bring the project up to*/
/* date.*/
/* */
/* (3) Build Code Resource. */
/* */
/* (4) Use ResEdit to copy the   */
/* resource to your stack.*/
/********************************/

#include<MacTypes.h>
#include<OSUtil.h>
#include<MemoryMgr.h>
#include<FileMgr.h>
#include<ResourceMgr.h>
#include  “HyperXCmd.h”

pascal void main( paramPtr )
 XCmdBlockPtr  paramPtr;
{
 char theString[256];/* A “Pascal” String */

 theString[0] = ‘\0x0B’;  /* Remember, static*/
 theString[1] = ‘H’; /* strings are placed*/
 theString[2] = ‘E’; /* in the global pool*/
 theString[3] = ‘L’; /* CODE resources such */
 theString[4] = ‘L’; /* as XCMDS and XFCNS*/
 theString[5] = ‘O’; /* don’t have access to */
 theString[6] = ‘ ‘; /* globals so you have*/
 theString[7] = ‘W’; /* to discretely set the*/
 theString[8] = ‘O’; /* string’s value */
 theString[9] = ‘R’;
 theString[10]= ‘L’;
 theString[11]= ‘D’;

 /* A sample callback example */
 paramPtr->returnValue = PasToZero( paramPtr, &theString );
}
Listing 2:

/************************************/
/* File:HyperXCmd.h  */
/* */
/* Interface for standard */ 
/* HyperCard callback routines.    */
/* */
/* Based on original work by*/
/* Dan Winkler of Apple Computer */
/* */
/************************************/

typedef struct Str31 {
 char data[32];
 } Str31;
typedef  Str31 * Str31Ptr;

typedef struct XCmdBlock {
 short  paramCount;       
    Handle  params[16];
    Handle  returnValue;      
    Boolean passFlag; 
    
    void  (*entryPoint)();    
    short request;  
    short result;  
    longinArgs[8];
    longoutArgs[4];
} XCmdBlock;
typedef XCmdBlock*XCmdBlockPtr; 

  /* Callback codes  */
#define xresSucc 0
#define xresFail 1 
#define xresNotImp 2 
  
  /* Callback request codes */
#define xreqSendCardMessage 1 
#define xreqEvalExpr 2 
#define xreqStringLength  3 
#define xreqStringMatch   4 

#define xreqZeroBytes         6 
#define xreqPasToZero7 
#define xreqZeroToPas8 
#define xreqStrToLong9 
#define xreqStrToNum 10 
#define xreqStrToBool11 
#define xreqStrToExt 12 
#define xreqLongToStr13 
#define xreqNumToStr 14 
#define xreqNumToHex 15 
#define xreqBoolToStr16 
#define xreqExtToStr 17 
#define xreqGetGlobal18 
#define xreqSetGlobal19 
#define xreqGetFieldByName20 
#define xreqGetFieldByNum 21 
#define xreqGetFieldByID  22 
#define xreqSetFieldByName23 
#define xreqSetFieldByNum 24 
#define xreqSetFieldByID  25 
#define xreqStringEqual       26 
#define xreqReturnToPas       27 
#define xreqScanToReturn      28 
#define xreqScanToZero        39  

/* 
 “Prototypes” for the Callbacks.  Project 
 must include XCmdGlue.c.  
*/

 
pascal void SendCardMessage();     
pascal Handle  EvalExpr();
pascal long StringLength(); 
pascal Ptr  StringMatch();
pascal void ZeroBytes();
pascal Handle  PasToZero();
pascal void ZeroToPas();
pascal long StrToLong();
pascal long StrToNum();
pascal Boolean   StrToBool();
pascal void StrToExt();
pascal void LongToStr();
pascal void NumToStr();
pascal void NumToHex();
pascal void BoolToStr();
pascal void ExtToStr();
pascal Handle  GetGlobal();
pascal void SetGlobal();
pascal Handle  GetFieldByName();
pascal Handle  GetFieldByNum();
pascal Handle  GetFieldByID();
pascal void SetFieldByName();
pascal void SetFieldByNum();
pascal void SetFieldByID();
pascal Boolean   StringEqual();
pascal void ReturnToPas();
pascal void ScanToReturn();
pascal void ScanToZero();
Listing 3:

/************************************/
/* File: XCMDGlue.c*/
/* */
/* Callback routines for XCMDs*/
/* and XFCNs.  This file should  */
/* be included in your project*/
/* */
/* Based on original work by*/
/* Dan Winkler of Apple Computer */
/* */
/************************************/

#include<MacTypes.h>
#include<OSUtil.h>
#include<MemoryMgr.h>
#include<FileMgr.h>
#include<ResourceMgr.h>
#include  “HyperXCmd.h”
#include<math.h>

pascal void SendCardMessage(paramPtr,msg)
 XCmdBlockPtr  paramPtr;  
 StringPtrmsg;
/***********************
* Send a message back to 
* hypercard.  The input message
* is a Pascal String
***********************/
{
 paramPtr->inArgs[0] = (long)msg;
 paramPtr->request = xreqSendCardMessage;
    CallPascal( paramPtr->entryPoint );
}

pascal Handle EvalExpr(paramPtr,expr)
 XCmdBlockPtr  paramPtr;  
 StringPtrexpr;
/***********************
* Evaluate a Hypertalk expression
* returning the result as a “C” 
* string
***********************/
{
 paramPtr->inArgs[0] = (long)expr;
 paramPtr->request = xreqEvalExpr;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal long StringLength(paramPtr,strPtr)
 XCmdBlockPtr  paramPtr;
 StringPtrstrPtr;
/***********************
* Counts the number of 
* characters in the input 
* string from StrPtr to end
* of string (zero byte)
***********************/
{
 paramPtr->inArgs[0] = (long)strPtr;
 paramPtr->request = xreqStringLength;
    CallPascal( paramPtr->entryPoint );
 return (long)paramPtr->outArgs[0];
}

pascal Ptr StringMatch(paramPtr,pattern,target)
 XCmdBlockPtr  paramPtr;  
 StringPtrpattern;
 Ptr    target;
/***********************
* Case-insensitive match 
* for pattern anywhere in
* target, 
* 
* Returns a pointer to first
* character of the first match,
* in target or NIL if no match
* found.  pattern is a Pascal string,
* and target is a zero-terminated string.
***********************/
{
 paramPtr->inArgs[0] = (long)pattern;
 paramPtr->inArgs[1] = (long)target;
 paramPtr->request = xreqStringMatch;
    CallPascal( paramPtr->entryPoint );
 return (Ptr)paramPtr->outArgs[0];
}

pascal void ZeroBytes(paramPtr,dstPtr,longCount)
 XCmdBlockPtr  paramPtr;  
 Ptr    dstPtr;  
 long   longCount;
/***********************
* Clear memory starting at destPtr
* through destPtr+longCount
***********************/
{
 paramPtr->inArgs[0] = (long)dstPtr;
 paramPtr->inArgs[1] = longCount;
 paramPtr->request = xreqZeroBytes;
    CallPascal( paramPtr->entryPoint );
}

pascal Handle PasToZero(paramPtr,pasStr)
 XCmdBlockPtr  paramPtr;
 StringPtrpasStr;
/***********************
* Convert a Pascal string (STR255)
* to a zero-terminated string.  
* Returns a handle to a zero-terminated
* string.  The caller must dispose the handle.
*
* Useful for setting the result or
* an argument you send from 
* an XCMD to HyperTalk.
***********************/
{
 paramPtr->inArgs[0] = (long)pasStr;
 paramPtr->request = xreqPasToZero;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal void ZeroToPas(paramPtr,zeroStr,pasStr)
 XCmdBlockPtr  paramPtr;  
 char   *zeroStr;
 StringPtrpasStr;
/***********************
* Copy the zero-terminated
* string into the Pascal String.
*
* You create the Pascal string 
* and pass it by reference.
*
***********************/
{
 paramPtr->inArgs[0] = (long)zeroStr;
 paramPtr->inArgs[1] = (long)pasStr;
 paramPtr->request = xreqZeroToPas;
    CallPascal( paramPtr->entryPoint );
}

pascal long StrToLong(paramPtr,strPtr)
 XCmdBlockPtr  paramPtr;  
 Str31  *strPtr;
/***********************
* Convert a string of ASCII
* characters to an unsigned 
* long integer.
***********************/
{
 paramPtr->inArgs[0] = (long)strPtr;
 paramPtr->request = xreqStrToLong;
    CallPascal( paramPtr->entryPoint );
 return (long)paramPtr->outArgs[0];
}

pascal long StrToNum(paramPtr,str)
 XCmdBlockPtr  paramPtr;  
 Str31  *str;
/***********************
* Convert a string of ASCII
* characters to a signed 
* long integer.
***********************/
{
 paramPtr->inArgs[0] = (long)str;
 paramPtr->request = xreqStrToNum;
    CallPascal( paramPtr->entryPoint );
 return paramPtr->outArgs[0];
}

pascal Boolean StrToBool(paramPtr,str)
 XCmdBlockPtr  paramPtr;
 Str31  *str;
/***********************
* Convert the Pascal strings
* ‘true’ and ‘false’ to booleans.
***********************/
{
 paramPtr->inArgs[0] = (long)str;
 paramPtr->request = xreqStrToBool;
    CallPascal( paramPtr->entryPoint );
 return (Boolean)paramPtr->outArgs[0];
}

pascal void StrToExt(paramPtr,str,myext)
 XCmdBlockPtr  paramPtr;
 Str31  *str;  
 long   *myext;
/***********************
* Convert a string of ASCII digits 
* to an extended long integer.
*
* The return value is passed
* by reference and you must
* asllocate the space before 
* calling this routine.
***********************/
{
 paramPtr->inArgs[0] = (long)str;
 paramPtr->inArgs[1] = (long)myext;
 paramPtr->request = xreqStrToExt;
    CallPascal( paramPtr->entryPoint );
}

pascal void LongToStr(paramPtr,posNum,mystr)
 XCmdBlockPtr  paramPtr;  
 long   posNum;  
 Str31  *mystr;
/***********************
* Convert an unsigned long integer
* to a pascal string representation
* Useful for sending numbers back 
* to Hypercard.
*
*  You create mystr and pass
* it by reference.
***********************/
{
 paramPtr->inArgs[0] = (long)posNum;
 paramPtr->inArgs[1] = (long)mystr;
 paramPtr->request = xreqLongToStr;
    CallPascal( paramPtr->entryPoint );
}

pascal void NumToStr(paramPtr,num,mystr)
 XCmdBlockPtr  paramPtr;  
 long   num;
 Str31  *mystr;
/***********************
* Convert a signed long integer
* to a pascal string representation
* Useful for sending numbers back 
* to Hypercard.
*
*  You create mystr and pass
* it by reference.
***********************/
{
 paramPtr->inArgs[0] = num;
 paramPtr->inArgs[1] = (long)mystr;
 paramPtr->request = xreqNumToStr;
    CallPascal( paramPtr->entryPoint );
}

pascal void NumToHex(paramPtr,num,nDigits,mystr)
 XCmdBlockPtr  paramPtr;  
 long   num;
 short  nDigits; 
 Str31  *mystr;
/***********************
* Convert an unsigned long integer
* to a hexadecimal number and put it
* into a Pascal string.
*
* The “output” string is passed
* by reference.
***********************/
{
 paramPtr->inArgs[0] = num;
 paramPtr->inArgs[1] = nDigits;
 paramPtr->inArgs[2] = (long)mystr;
 paramPtr->request = xreqNumToHex;
    CallPascal( paramPtr->entryPoint );
}

pascal void BoolToStr(paramPtr,bool,mystr)
 XCmdBlockPtr  paramPtr;  
 Booleanbool;  
 Str31  *mystr;
/***********************
* Convert a boolean to 
* ‘true’ or ‘false’.  
*
* The “output” string is passed
* by reference.
***********************/
{
 paramPtr->inArgs[0] = (long)bool;
 paramPtr->inArgs[1] = (long)mystr;
 paramPtr->request = xreqBoolToStr;
    CallPascal( paramPtr->entryPoint );
}

pascal void ExtToStr( paramPtr, myext, mystr)
 XCmdBlockPtr  paramPtr;  
 char   *myext;  
 Str31  *mystr;
/***********************
* Convert an extended long
* to its string representation
*
* The “output” string is passed
* by reference.
***********************/
{
 paramPtr->inArgs[0] = (long)myext;
 paramPtr->inArgs[1] = (long)mystr;
 paramPtr->request = xreqExtToStr;
    CallPascal( paramPtr->entryPoint );
}

pascal Handle GetGlobal(paramPtr,globName)
 XCmdBlockPtr  paramPtr;  
 StringPtrglobName;
/***********************
* Return a handle to a zero-terminated
* string containing the value of 
* the specified HyperTalk global variable.
***********************/
{
 paramPtr->inArgs[0] = (long)globName;
 paramPtr->request = xreqGetGlobal;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal void SetGlobal(paramPtr,globName,globValue)
 XCmdBlockPtr  paramPtr;  
 StringPtrglobName;
 Handle globValue;
/***********************
* Set the value of the specified 
* HyperTalk global variable to be
* the zero-terminated string in globValue.
* The contents of globValue
* are copied, you dispose the
* handle
***********************/
{
 paramPtr->inArgs[0] = (long)globName;
 paramPtr->inArgs[1] = (long)globValue;
 paramPtr->request = xreqSetGlobal;
    CallPascal( paramPtr->entryPoint );
}

pascal Handle GetFieldByName(paramPtr,cardFieldFlag,fieldName)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 StringPtrfieldName;
/***********************
* Return a handle to a zero-terminated
* string containing the value of 
* field fieldName on the current 
* card.  You must dispose the handle.
*
* Set cardfieldFlag to ture if
* you want the contents of a card
* field or to false if you want
* the contents of a bkgnd field
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = (long)fieldName;
 paramPtr->request = xreqGetFieldByName;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal Handle GetFieldByNum(paramPtr,cardFieldFlag,fieldNum)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 short  fieldNum;
/***********************
* Returns a copy of the contents of the field whose number is
* fieldnum on the current card.
* You dispose the handle when you are done.
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = fieldNum;
 paramPtr->request = xreqGetFieldByNum;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal Handle GetFieldByID(paramPtr,cardFieldFlag,fieldID)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 short  fieldID;
/***********************
* Returns a copy of the contents of the field whose id is
* fieldID on the current card.
* You dispose the handle when you are done.
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = fieldID;
 paramPtr->request = xreqGetFieldByID;
    CallPascal( paramPtr->entryPoint );
 return (Handle)paramPtr->outArgs[0];
}

pascal void SetFieldByName(paramPtr,cardFieldFlag,fieldName,fieldVal)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 StringPtrfieldName; 
 Handle fieldVal;
/***********************
* Set the value of the field whose name is fieldName on 
* the current card.
* You dispose the handle when you are done.
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = (long)fieldName;
 paramPtr->inArgs[2] = (long)fieldVal;
 paramPtr->request = xreqSetFieldByName;
    CallPascal( paramPtr->entryPoint );
}

pascal void SetFieldByNum(paramPtr,cardFieldFlag,fieldNum,fieldVal)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 short  fieldNum;
 Handle fieldVal;
/***********************
* Set the value of the field whose number is fieldnum on 
* the current card.
* You dispose the handle when you are done.
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = fieldNum;
 paramPtr->inArgs[2] = (long)fieldVal;
 paramPtr->request = xreqSetFieldByNum;
    CallPascal( paramPtr->entryPoint );
}

pascal void SetFieldByID(paramPtr,cardFieldFlag,fieldID,fieldVal)
 XCmdBlockPtr  paramPtr;  
 BooleancardFieldFlag;
 short  fieldID; 
 Handle fieldVal;
/***********************
* Set the value of the field whose id is fieldID on 
* the current card.
* You dispose the handle when
* you are done.
***********************/
{
 paramPtr->inArgs[0] = (long)cardFieldFlag;
 paramPtr->inArgs[1] = fieldID;
 paramPtr->inArgs[2] = (long)fieldVal;
 paramPtr->request = xreqSetFieldByID;
    CallPascal( paramPtr->entryPoint );
}

pascal Boolean StringEqual(paramPtr,str1,str2)
 XCmdBlockPtr  paramPtr;  
 Str31  *str1; 
 Str31  *str2;
/***********************
* Returns true if the strings match, false otherwise.
* Compare is case insensitive
***********************/
{
 paramPtr->inArgs[0] = (long)str1;
 paramPtr->inArgs[1] = (long)str2;
 paramPtr->request = xreqStringEqual;
    CallPascal( paramPtr->entryPoint );
 return (Boolean)paramPtr->outArgs[0];
}

pascal void ReturnToPas(paramPtr,zeroStr,pasStr)
 XCmdBlockPtr  paramPtr;  
 Ptr    zeroStr; 
 StringPtrpasStr;
/***********************
* Collect characters from zeroStr
* to the next carriage Return and return 
* them in the Pascal string pasStr. 
* If no Return found, collect chars
* until the end of the string (zero)
***********************/
{
 paramPtr->inArgs[0] = (long)zeroStr;
 paramPtr->inArgs[1] = (long)pasStr;
 paramPtr->request = xreqReturnToPas;
    CallPascal( paramPtr->entryPoint );
}

pascal void ScanToReturn(paramPtr,scanHndl)
 XCmdBlockPtr  paramPtr;  
 Ptr    *scanHndl;
/***********************
* Position the pointer, scanPtr,at a Return character
* or a zero byte. 
***********************/
{
 paramPtr->inArgs[0] = (long)scanHndl;
 paramPtr->request = xreqScanToReturn;
    CallPascal( paramPtr->entryPoint );
}

pascal void ScanToZero(paramPtr,scanHndl)
 XCmdBlockPtr  paramPtr;  
 Ptr    *scanHndl;
/***********************
* Position the pointer, scanPtr,
* at a  zero byte. 
***********************/
{
 paramPtr->inArgs[0] = (long)scanHndl;
 paramPtr->request = xreqScanToZero;
    CallPascal( paramPtr->entryPoint );
}

 
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Download the patch by launching the Starcraft II game and downloading it through the Battle.net connection within the app. Starcraft II: Wings of Liberty is a strategy game played in real-time. You... Read more
Sibelius 7.5.0 - Music notation solution...
Sibelius is the world's best-selling music notation software for Mac. It is as intuitive to use as a pen, yet so powerful that it does most things in less than the blink of an eye. The demo includes... Read more
Typinator 5.9 - Speedy and reliable text...
Typinator turbo-charges your typing productivity. Type a little. Typinator does the rest. We've all faced projects that require repetitive typing tasks. With Typinator, you can store commonly used... Read more
MYStuff Pro 2.0.16 - Create inventories...
MYStuff Pro is the most flexible way to create detail-rich inventories for your home or small business. Add items to MYStuff by dragging and dropping existing information, uploading new images, or... Read more

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Have a Special Dead Trigger 2 Easter Bas...
Have a Special Dead Trigger 2 Easter Basket Full of Goodies, Courtesy of Madfinger Games Posted by Rob Rich on April 18th, 2014 [ permalink ] Dead Trigger 2 | Read more »
Zynga Launches Brand New Farmville Exper...
Zynga Launches Brand New Farmville Experience with Farmville 2: Country Escape Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
David. Review
David. Review By Cata Modorcea on April 18th, 2014 Our Rating: :: MINIMALISTIC IN A DIFFERENT WAYUniversal App - Designed for iPhone and iPad David is a minimalistic game wrapped inside of a soothing atmosphere in which the hero... | Read more »
Eyefi Unveils New Eyefi Cloud Service Th...
Eyefi Unveils New Eyefi Cloud Service That Allows Users to Share Media Across Personal Devices Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
Tales from the Dragon Mountain: The Lair...
Tales from the Dragon Mountain: The Lair Review By Jennifer Allen on April 18th, 2014 Our Rating: :: STEADY ADVENTURINGiPad Only App - Designed for the iPad Treading a safe path, Tales from the Dragon Mountain: The Lair is a... | Read more »
Yahoo Updates Flickr App with Advanced E...
Yahoo Updates Flickr App with Advanced Editing Features and More Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
My Incredible Body - A Kid's App to...
My Incredible Body - A Kid's App to Learn about the Human Body 1.1.00 Device: iOS Universal Category: Education Price: $2.99, Version: 1.1.00 (iTunes) Description: Wouldn’t it be cool to look inside yourself and see what was going on... | Read more »
Trials Frontier Review
Trials Frontier Review By Carter Dotson on April 18th, 2014 Our Rating: :: A ROUGH LANDINGUniversal App - Designed for iPhone and iPad Trials Frontier finally brings the famed stunt racing franchise to mobile, but how much does its... | Read more »
Evernote Business Notebook by Moleskin I...
Evernote Business Notebook by Moleskin Introduced – Support Available in Evernote for iOS Posted by Tre Lawrence on April 18th, 2014 [ permalink ] | Read more »
Sparkle Unleashed Review
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Price Scanner via MacPrices.net

iMacs on sale for up to $160 off MSRP this we...
Best Buy has iMacs on sale for up to $160 off MSRP for a limited time. Choose free home shipping or free instant local store pickup (if available). Prices are valid for online orders only, in-store... Read more
iPad Airs on sale this weekend for up to $100...
Best Buy has WiFi iPad Airs on sale for $50 off MSRP and WiFi + Cellular iPad Airs on sale for $100 off MSRP on their online store for a limited time, with prices now starting at $449. Choose free... Read more
Apple restocks refurbished Mac minis starting...
The Apple Store has restocked Apple Certified Refurbished Mac minis for up to $150 off the cost of new models. Apple’s one-year warranty is included with each mini, and shipping is free: - 2.5GHz Mac... Read more
Hyundai Brings Apple CarPlay To The 2015 Sona...
Hyundai Motor America has announced it will bring Apple CarPlay functionality to the 2015 Sonata. CarPlay is pitched as a smarter, safer and easier way to use iPhone in the car and gives iPhone users... Read more
Updated iPads Coming Sooner Than We Had Thoug...
MacRumors, cites KGI securities analyst Ming Chi Kuo, well-respected as an Apple product prognisticator, saying that Apple will introduce an upgraded iPad Air and iPad mini in 2014/Q3, meaning the... Read more
Toshiba Unveils New High And Low End Laptop M...
Toshiba has announced new laptop models covering both the high-end and low-end of the notebook computer spectrum. Toshiba 4K Ultra HD Laptop Toshiba’s new Satellite P55t features one of the world’s... Read more
Save up to $270 with Apple refurbished 13-inc...
The Apple Store has Apple Certified Refurbished October 2013 13″ Retina MacBook Pros available starting at $1099, with models up to $270 off MSRP. Apple’s one-year warranty is standard, and shipping... Read more
Apple now offering refurbished iPad mini with...
The Apple Store has Certified Refurbished 2nd generation iPad minis with Retina Displays now available starting at $339. Apple’s one-year warranty is included with each model, and shipping is free.... Read more
Microsoft Blinks – Drops Microsoft Office 365...
Microsoft has dropped the annual subscription fee for Microsoft Office 365 Personal – which is needed in order to create and edit documents in Microsoft Office for iPad. However, Apple’s iOS and OS X... Read more
New AVG Vault Apps for iOS and Android Help K...
AVG Technologies N.V. an online security company for 177 million active users, has announced the launch of its latest mobile application, AVG Vault. The free app introduces an innovative user... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Retail - Manager - Holyoke - Apple I...
Job Summary Keeping an Apple Store thriving requires a diverse set of leadership skills, and as a Manager, you’re a master of them all. In the store’s fast-paced, Read more
*Apple* Retail - Manager - Apple (United Sta...
Job SummaryKeeping an Apple Store thriving requires a diverse set of leadership skills, and as a Manager, you're a master of them all. In the store's fast-paced, dynamic Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Retail - Market Leader - Cincinnati...
…challenges of developing individuals, building teams, and affecting growth across Apple Stores. You demonstrate successful leadership ability - focusing on excellence Read more
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