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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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Adium is a fast and free instant messaging client which supports AIM, ICQ, Jabber, MSN, Yahoo!, Google Talk, Yahoo! Japan, Bonjour, Gadu-Gadu, Novell Groupwise, SIP/SIMPLE (Text), and Lotus Sametime... Read more
File Juicer 4.57 - $18.00
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
WhatsApp 0.2.4238 - Desktop client for W...
WhatsApp is the desktop client for WhatsApp Messenger, a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS. WhatsApp Messenger is available for... Read more

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Olli by Tinrocket (Photography)
Olli by Tinrocket 1.0 Device: iOS iPhone Category: Photography Price: $2.99, Version: 1.0 (iTunes) Description: Get drawn in with Olli by TinrocketOlli instantly turns your everyday moments into hand-drawn art and animations. • Watch... | Read more »
Penarium (Games)
Penarium 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: | Read more »
Fire Emblem Heroes is way more profitabl...
Profits for Nintendo's mobile game Fire Emblem Heroes are apparently impressive enough to beat out other Nintendo titles likeSuper Mario Run, despite having 10 times fewer downloads. [Read more] | Read more »
Classic series Robot Unicorn Attack 3 no...
The classic Adult Swim browser game, Robot Unicorn Attack, branched off into a series of popular mobile games. Now, the latest entry into the series, Robot Unicorn Attack 3, is available for iOS and Android mobile devices. [Read more] | Read more »
Sudoku Sweeper (Games)
Sudoku Sweeper 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: A minimalist mashup of Minesweeper and Sudoku. Logic puzzle perfection. Every row, column and zone contains a bomb and one of... | Read more »
Under Leaves (Games)
Under Leaves 1.0.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.0 (iTunes) Description: Journey into the forest, the jungle or the depths of the deep blue sea. Find chestnuts for the pigs, a caterpillar for the... | Read more »
Ninja Pizza Girl (Games)
Ninja Pizza Girl 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: In the not-so-distant future, rampart traffic congestion has resulted in only one way to deliver pizzas across town in thirty... | Read more »
SCRAP (Games)
SCRAP 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: That day, for no apparent reason, SCRAP decided to wake up and run. He had to, because his activation was a mistake the "Factory" could... | Read more »
The Bunker (Games)
The Bunker 1.1 Device: iOS Universal Category: Games Price: $3.99, Version: 1.1 (iTunes) Description: The critically acclaimed console hit "The Bunker" comes to iOS, The groundbreaking live-action thriller adventure set in a real... | Read more »
Die With Glory (Games)
Die With Glory 1.2.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.2.0 (iTunes) Description: Die with Glory is an epic adventure game where your goal is to die in glorious fashion. You must help Sigurd, a brave old... | Read more »

Price Scanner via MacPrices.net

New System Clock for macOS by B-Eng Now Avail...
Fehraltorf, Switzerland based B-Eng has announced the release and immediate availability of System Clock, the company’s new system monitor and information app developed exclusively for macOS. System... Read more
DEVONtechnologies Celebrates 15th Anniversary...
DEVONtechnologies celebrates its 15th company anniversary with a 30% discount on all its software products from May 1st through 5th, 2017. In spring 2002, DEVONtechnologies opened its website and... Read more
WaterField Designs Invites Customers to Help...
San Francisco based WaterField Designs invites customers and air travelers to participate in developing the next generation in-flight travel case, the Air Porter. Frustrated with limited legroom,... Read more
Save up to $260 with Apple refurbished 12-inc...
Apple has Certified Refurbished 2016 12″ Retina MacBooks available for $200-$260 off MSRP. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The following... Read more
Digital Paper Tablet Offers Distraction Free...
I typically spend 8-10 hours a day gazing at the screens in my laptops and iPad, as tools of my livelihood, I don’t as a rule use electronic devices for pleasure reading. I subscribe to a daily... Read more
“Today at Apple” Bringing New Educational Ses...
Apple has announced plans to launch dozens of new educational sessions next month in all 495 Apple Stores ranging in topics from photo and video to music, coding, art and design, and more. The hands-... Read more
Smart Finance Free Comprehensive Personal Fin...
Moscow-based indie developer, Alexander Survillo has announced the release and immediate availability of Smart Finance: Personal Finance, Budget & Money 1.1.4, an update to his comprehensive... Read more
12-inch 1.1GHz Retina MacBooks on sale for $1...
B&H has 12″ 1.1GHz Retina MacBooks on sale for $100 off MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: - 12″ 1.1GHz Space Gray Retina MacBook: $1199.99 $100 off MSRP - 12... Read more
13-inch 2.7GHz Retina MacBook Pro on sale for...
B&H Photo has the 13″ 2.7GHz Retina MacBook Pro on sale for $130 off MSRP. Shipping is free, and B&H charges NY & NJ tax only: - 13″ 2.7GHz/128GB Retina MacBook Pro (MF839LL/A): $1169 $... Read more
15-inch 2.2GHz Retina MacBook Pros available...
B&H Photo has the 15″ 2.2GHz Retina MacBook Pro available for $200 off MSRP including free shipping plus NY & NJ sales tax only: - 15″ 2.2GHz Retina MacBook Pro (MJLQ2LL/A): $1799.99 $200 off... Read more

Jobs Board

*Apple* Mac Computer Technician - GeekHampto...
…complex computer issues over the phone and in person? GeekHampton, Long Island's Apple Premium Service Provider, is looking for you! Come work with our crew Read more
*Apple* Retail - Multiple Positions- Chicago...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Systems Engineer - California Polyte...
Cal Poly, San Luis Obispo Apple Systems Engineer Department: ITS - Customer & Tech Support (134900) College/Division: Academic Affairs Salary Range: Position Read more
*Apple* Mobile Master - Best Buy (United Sta...
**501042BR** **Job Title:** Apple Mobile Master **Location Number:** 000416-East Lansing-Store **Job Description:** **What does a Best Buy Apple Mobile Master Read more
Best Buy *Apple* Computing Master - Best Bu...
**501195BR** **Job Title:** Best Buy Apple Computing Master **Location Number:** 000211-Colorado Blvd-Store **Job Description:** **What does a Best Buy Apple Read more
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