TweetFollow Us on Twitter

HyperCard 2.0
Volume Number:6
Issue Number:11
Column Tag:XCMD Corner

HyperCard 2.0

By Donald Koscheka, MacTutor Contributing Editor

The Revolution

Thomas Jefferson once stated that “Revolution is that event which allows all ordinary events to continue”. Based on this definition, I’m inclined to feel that HyperCard 2.0 is a bit revolutionary. For the past 3 years, stack developers have expended a tremendous amount of energy trying to squeeze the last bit of performance from HyperCard.

This effort almost always leads to the development of some suite of XCMDs to supercharge an existing stack. As I watched this evolution develop, I noticed that XCMDs typically fall along a specific set of tasks. These include file I/O, interfacing to external devices, print management and window management (including dialogs). From the perspective of the XCMD programmer, the HyperCard 2.0 revolution is not at all subtle: HyperCard incorporates many features found previously only in XCMDs.

HyperCard 2.0 brings more to the party than new XCMD capability but in keeping with the spirit of this column, I will focus on what’s new in the XCMD world.

What’s New and What’s Not

Whenever you need to develop for a new version of any software package, you need to evaluate the scope of the update. You can perform this evaluation very quickly by asking yourself two questions: “What changed since the last version” and “What hasn’t changed since the last version?”

Armed with these two questions, the best place to find the answers is in the interface and library files in HyperCard 2.0. My version of HyperCard 2.0 came with just 3 files: HyperXCMD.p, HyperXCMD.h and HyperXlib.o. I was immediately surprised to find that XCMDGlue was missing from the distribution disk. At first I thought this was a mistake but a quick disassembly of HyperXLib.o showed this not to be the case; XCMDGlue is no longer needed, that function is now performed directly in the Callback Library.

So the first change is that we no longer need to compile our code with a glue routine. The interface code varies incrementally beyond this point (that is, they’ve ADDED stuff but all of the old stuff is still intact). For example, XCMDs are still called with the same parameter block record as in earlier versions of HyperCard with the exception that the the fields in the block take on special meaning for external windows. External windows adds a whole new dimension to HyperCard so look for a lot of discussion about them in future installments of this column.

The parameter block is not only used for interfacing between the calling script and the XCMD but also for interfacing between the XCMD and the HyperCard callbacks. The callback engine has been increased to over 75 callbacks (I counted two callbacks that appear in the library but are not documented as of this writing). The new callbacks can be divided into groups according to the class of services they perform: Hypertalk utilities, Memory Utilities, String Utilities, String Conversions, field utilities, miscellaneous utilities, Creating and disposing windows, window utilities, text edit utilities, script editor utilities, debugging tools. The categories are Apple’s, not mine. I will use this list to set the agenda for this column for the next several months. We will look at each of these categories in detail in turn.

One of the most salient additions to XCMDs in HyperCard 2.0 is the addition of “version control” information. From now, whenever the user passes ! as the first parameter to an xcmd, you need to return the version of that XCMD. if the user types passes ? as the first parameter, you should pass usage information to the user. This is straightforward and simple enough to abide by. Funny how those darned “command lines” have a habit of appearing in the most unusual of places. With this in mind, we will start at the beginning again, introducing “Simple XCMD 2.0.c” with this new twist. This is the building block for all 2.0 XCMDs and you can use it as a sort of template. A controversy will no doubt arise over the hard coding of strings in the XCMD code resource, but without a lot of thought, I think that you can convince yourself that there isn’t a better way to do this.

An XCMD For 2.0

While we haven’t answered both questions in great detail on this pass, we have learned enough to jump right into trying our hand at an XCMD for 2.0. We learned that the interface is pretty much unchanged and that old XCMD should work fine under 2.0 although they won’t be able to take advantage of 2.0’s features. Most importantly, we learned that this isn’t a complete restart; we can easily build on existing experience as we migrate our code to 2.0. This is good -- nobody likes to spend 3 years doing anything just to discover on such and such a date that everything they know is wrong!

Listing 1 is a sample HyperCard 2.0 XCMD. It is quite straightforward since it doesn’t actually do anything. I am taking the introduction of HyperCard 2.0 as a rare opportunity to “wipe the slate clean” and start all over again with a fresh look at XCMDs. Since this is the first of many columns in which I will discuss 2.0, I have decided to start off slow and sure and build from here. Listing 1 conforms to the structure of a 2.0 XCMD without relying on the new XCMD glue. If you don’t have 2.0 yet, you can build and test this XCMD under earlier versions of HyperCard until you get version 2.0. I did this to allow those of you who want to follow along with this column to get caught up first. I will start in earnest on 2.0 next month. Until then, Happy Hacking!

/**********************************/
/* File: Sample.c*/
/* */
/* A sample XCMD for Hypercard*/
/* 2.0  */
/* */
/* Well-behaved XCMDs for HC2.0  */
/* will respond to the ! and ?*/
/* requests by returning version */
/* and usage information  */
/* respectively. */
/* */
/* ----------------------------  */
/* ©1990, Donald Koscheka */
/* All Rights Reserved    */
/**********************************/

/*
 Project:

 ANSI-A4-- standard “C” libraries assembled
 off of register A4
 
 MacTraps
 Sample2.0.c (contents of listing 1)

 Set Project Type:
 Type == XCMD | XFCN
 Name == SimpleXCMD
 id == 1000
 
 Usage
 
 SimpleXCMD “?”
 SimpleXCMD “!”
 put the result
 
 OR
 
 Put simpleXCMD( “?” )
 Put simpleXCMD( “!” )
*/

#include<SetUpA4.h>
#include<string.h>
#include<HyperXCMD.h>
 
#ifndef NIL
 #define NIL(void *)0L
#endif

Handle  strToParam( str )
 char *str;
/***************************
* Given a pointer to a string,
* copy that string into a handle
* and return the handle.
*
* The input and output strings
* are both null-terminated
*
***************************/
{
 Handle outH = NIL;
 long len = 0;
 
 len = strlen( str );
 if( len )
 if( outH = NewHandle( len ) )
 BlockMove( str, *outH, len + 1 );
 
 return( outH );
}

pascal void main( paramPtr )
 XCmdPtrparamPtr;
{
 Handle answer = NIL;
 char *str;
 long len;
 
 paramPtr->returnValue = NIL;

 /** The first thing that a well-behaved           **/
 /** HC2.0 XCMD should do is check to see    **/
 /** whether the first (and only) parameter  **/
 /** is the user request for information or  **/
 /** or usage information.  If so, just pass **/
 /** your answer back to the user, otherwise **/
 /** go ahead and perform your xcmd services **/
 
 if (paramPtr->paramCount == 1){
 if ( **(paramPtr->params[0]) == ‘!’ ){
 paramPtr->returnValue = strToParam(“Simple XCMD, version 1.0, ©Donald 
Koscheka, 1990”);
 return;
 }
 
 if ( **(paramPtr->params[0]) == ‘?’ ){
 paramPtr->returnValue = strToParam(“Simple takes no parameters and does 
nothing with them.”);
 return;
 }
 }
}

Listing 1. SimpleXCMD.c

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Skype 7.5.0.738 - Voice-over-internet ph...
Skype allows you to talk to friends, family and co-workers across the Internet without the inconvenience of long distance telephone charges. Using peer-to-peer data transmission technology, Skype... Read more
PushPal 3.0 - Mirror Android notificatio...
PushPal is a client for Pushbullet, which automatically shows you all of your phone's notifications right on your computer. This means you can see who's calling or read text messages even if your... Read more
Logic Pro X 10.1.1 - Music creation and...
Apple Logic Pro X is the most advanced version of Logic ever. Sophisticated new tools for professional songwriting, editing, and mixing are built around a modern interface that's designed to get... Read more
VLC Media Player 2.2.0 - Popular multime...
VLC Media Player is a highly portable multimedia player for various audio and video formats (MPEG-1, MPEG-2, MPEG-4, DivX, MP3, OGG, ...) as well as DVDs, VCDs, and various streaming protocols. It... Read more
Sound Studio 4.7.8 - Robust audio record...
Sound Studio lets you easily record and professionally edit audio on your Mac. Easily rip vinyls and digitize cassette tapes, or record lectures and voice memos. Prepare for live shows with live... Read more
LibreOffice 4.4.1.2 - Free, open-source...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
VueScan 9.5.03 - Scanner software with a...
VueScan is a scanning program that works with most high-quality flatbed and film scanners to produce scans that have excellent color fidelity and color balance. VueScan is easy to use, and has... Read more
Freeway Pro 7.0.3 - Drag-and-drop Web de...
Freeway Pro lets you build websites with speed and precision... without writing a line of code! With its user-oriented drag-and-drop interface, Freeway Pro helps you piece together the website of... Read more
Cloud 3.3.0 - File sharing from your men...
Cloud is simple file sharing for the Mac. Drag a file from your Mac to the CloudApp icon in the menubar and we take care of the rest. A link to the file will automatically be copied to your clipboard... Read more
Cyberduck 4.6.5 - FTP and SFTP browser....
Cyberduck is a robust FTP/FTP-TLS/SFTP browser for the Mac whose lack of visual clutter and cleverly intuitive features make it easy to use. Support for external editors and system technologies such... Read more

The first ever action 3D card battler Al...
On the other hand, you probably haven’t played an action 3D card battler – until now. Step forward, All Star Legion. All Star Legion is a 3D QTE-based action RPG card battler, but fear not – the game itself isn’t as convoluted as its description.... | Read more »
Travel Back to the 1980s With the Making...
Headup Games has released a hilarious making of video for its upcoming title, Pixel Heroes: Byte & Magic. The game is a RPG/Roguelike where you control three heroes set to save the township of Pixton from an evil cult called The Sons of Dawn.... | Read more »
Heavenstrike Rivals Review
Heavenstrike Rivals Review By Campbell Bird on March 2nd, 2015 Our Rating: :: HEAVENLY STRATEGICUniversal App - Designed for iPhone and iPad Despite a few flaws, this free-to-play strategy game is a fun mix of new and old strategy... | Read more »
Get The Whole Story – Lone Wolf Complete...
Get The Whole Story – Lone Wolf Complete is Now Available and On Sale Posted by Jessica Fisher on February 27th, 2015 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Who Wore it Best? The Counting Dead vs....
Like it or not, the “clicker” genre, popularized by cute distractions like Candy Box and Cookie Clicker, seems like it’s here to stay. So Who Wore it Best? takes a look at two recent examples: The Counting Dead and AdVenture Capitalist. | Read more »
Card Crawl, the Mini Deck Building Game,...
Card Crawl, the Mini Deck Building Game, is Coming Soon Posted by Jessica Fisher on February 27th, 2015 [ permalink ] Tinytouchtales and Mexer have announced their new game, | Read more »
Witness an all new puzzle mechanic in Bl...
Well, BlastBall MAX is not one of those games and is bucking trends such as timers, elements of randomness, and tacked-on mechanics in favor of pure puzzle gameplay. When you first boot up the game you’ll see a grid made up of squares that are each... | Read more »
This Princess Has a Dragon and She isn’t...
This Princess Has a Dragon and She isn’t Afraid to Useit. | Read more »
Mecha Showdown Review
Mecha Showdown Review By Lee Hamlet on February 27th, 2015 Our Rating: :: IN A SPINUniversal App - Designed for iPhone and iPad Mecha Showdown replaces traditional buttons with a slot machine mechanic in this robot fighting game,... | Read more »
Reliance Games and Dreamworks Unveil Rea...
Reliance Games and Dreamworks Unveil Real Steel Champions Posted by Ellis Spice on February 27th, 2015 [ permalink ] Reliance Games and Dreamworks have announced that a third game in | Read more »

Price Scanner via MacPrices.net

27-inch 3.5GHz 5K iMac in stock today and on...
 B&H Photo has the 27″ 3.5GHz 5K iMac in stock today and on sale for $2299 including free shipping plus NY sales tax only. Their price is $200 off MSRP, and it’s the lowest price available for... Read more
Apple Launches Free Web-Based Pages and Other...
Apple’s new Web-only access to iWork productivity apps is a free level of iCloud service available to anyone, including people who don’t own or use Apple devices. The service includes access to Apple... Read more
Survey Reveals Solid State Disk (SSD) Technol...
In a recent SSD technology use survey, Kroll Ontrack, a firm specializing in data recovery, found that while nearly 90 percent of respondents leverage the performance and reliability benefits of SSD... Read more
Save up to $600 with Apple refurbished Mac Pr...
The Apple Store is offering Apple Certified Refurbished Mac Pros for up to $600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The... Read more
Updated Mac Price Trackers
We’ve updated our Mac Price Trackers with the latest information on prices, bundles, and availability on systems from Apple’s authorized internet/catalog resellers: - 15″ MacBook Pros - 13″ MacBook... Read more
Apple CEO Tim Cook to Deliver 2015 George Was...
Apple CEO Tim Cook will deliver the George Washington University’s Commencement address to GWU grads on May 17, at which time he will also be awarded an honorary doctorate of public service from the... Read more
Apple restocks refurbished Mac minis for up t...
The Apple Store has restocked Apple Certified Refurbished 2014 Mac minis, with models available starting at $419. Apple’s one-year warranty is included with each mini, and shipping is free: - 1.4GHz... Read more
Save up to $50 on iPad Air 2s, NY tax only, f...
 B&H Photo has iPad Air 2s on sale for $50 off MSRP including free shipping plus NY sales tax only: - 16GB iPad Air 2 WiFi: $469.99 $30 off - 64GB iPad Air 2 WiFi: $549 $50 off - 128GB iPad Air 2... Read more
16GB iPad Air 2 on sale for $447, save $52
Walmart has the 16GB iPad Air 2 WiFi on sale for $446.99 on their online store for a limited time. Choose free shipping or free local store pickup (if available). Sale price for online orders only,... Read more
iMacs on sale for up to $205 off MSRP
B&H Photo has 21″ and 27″ iMacs on sale for up to $205 off MSRP including free shipping plus NY sales tax only: - 21″ 1.4GHz iMac: $1029 $70 off - 21″ 2.7GHz iMac: $1199 $100 off - 21″ 2.9GHz... Read more

Jobs Board

Sr. Technical Services Consultant, *Apple*...
**Job Summary** Apple Professional Services (APS) has an opening for a senior technical position that contributes to Apple 's efforts for strategic and transactional Read more
Event Director, *Apple* Retail Marketing -...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global engagement strategy and team. Delivering an overarching brand Read more
*Apple* Pay - Site Reliability Engineer - Ap...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
*Apple* Solutions Consultant - Retail Sales...
**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* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.