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

 
AAPL
$102.50
Apple Inc.
+0.25
MSFT
$45.43
Microsoft Corpora
+0.55
GOOG
$571.60
Google Inc.
+2.40

MacTech Search:
Community Search:

Software Updates via MacUpdate

pwSafe 3.1 - Secure password management...
pwSafe provides simple and secure password management across devices and computers. pwSafe uses iCloud to keep your password databases backed-up and synced between Macs and iOS devices. It is... Read more
StatsBar 1.8 - Monitor system processes...
StatsBar gives you a comprehensive and detailed analysis of the following areas of your Mac: CPU usage Memory usage Disk usage Network and bandwidth usage Battery power and health (MacBooks only)... Read more
Path Finder 6.5.5 - Powerful, award-winn...
Path Finder is a file browser that combines the familiar Finder interface with the powerful utilities and innovative features. Just a small selection of the Path Finder 6 feature set: Dual pane... Read more
QuarkXPress 10.2.1 - Desktop publishing...
With QuarkXPress, you can communicate in all the ways you need to -- and always look professional -- in print and digital media, all in a single tool. Features include: Easy to Use -- QuarkXPress is... Read more
Skype 6.19.0.450 - Voice-over-internet p...
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
VueScan 9.4.41 - 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
Cloud 3.0.0 - 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
LibreOffice 4.3.1.2 - Free Open Source o...
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
SlingPlayer Plugin 3.3.20.505 - Browser...
SlingPlayer is the screen interface software that works hand-in-hand with the hardware inside the Slingbox to make your TV viewing experience just like that at home. It features an array of... Read more
Get Lyrical 3.8 - Auto-magically adds ly...
Get Lyrical auto-magically add lyrics to songs in iTunes. You can choose either a selection of tracks, or the current track. Or turn on "Active Tagging" to get lyrics for songs as you play them.... Read more

Latest Forum Discussions

See All

Rhonna Designs Magic (Photography)
Rhonna Designs Magic 1.0 Device: iOS Universal Category: Photography Price: $1.99, Version: 1.0 (iTunes) Description: Want to sprinkle *magic* on your photos? With RD Magic, you can add colors, filters, light leaks, bokeh, edges,... | Read more »
This Week at 148Apps: August 25-29, 2014
Shiny Happy App Reviews   | Read more »
Qube Kingdom – Tips, Tricks, Strategies,...
Qube Kingdom is a tower defense game from DeNA. You rally your troops – magicians, archers, knights, barbarians, and others – and fight against an evil menace looking to dominate your kingdom of tiny squares. Planning a war isn’t easy, so here are a... | Read more »
Qube Kingdom Review
Qube Kingdom Review By Nadia Oxford on August 29th, 2014 Our Rating: :: KIND OF A SQUARE KINGDOMUniversal App - Designed for iPhone and iPad Qube Kingdom has cute visuals, but it’s a pretty basic tower defense game at heart.   | Read more »
Fire in the Hole Review
Fire in the Hole Review By Rob Thomas on August 29th, 2014 Our Rating: :: WALK THE PLANKUniversal App - Designed for iPhone and iPad Seafoam’s Fire in the Hole looks like a bright, 8-bit throwback, but there’s not enough booty to... | Read more »
Alien Creeps TD is Now Available Worldwi...
Alien Creeps TD is Now Available Worldwide Posted by Ellis Spice on August 29th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Dodo Master Review
Dodo Master Review By Jordan Minor on August 29th, 2014 Our Rating: :: NEST EGGiPad Only App - Designed for the iPad Dodo Master is tough but fair, and that’s what makes it a joy to play.   | Read more »
Motorsport Manager Review
Motorsport Manager Review By Lee Hamlet on August 29th, 2014 Our Rating: :: MARVELOUS MANAGEMENTUniversal App - Designed for iPhone and iPad Despite its depth and sense of tactical freedom, Motorsport Manager is one of the most... | Read more »
Motorsport Manager – Beginner Tips, Tric...
The world of Motorsport management can be an unforgiving and merciless one, so to help with some of the stress that comes with running a successful race team, here are a few hints and tips to leave your opponents in the dust. | Read more »
CalPal Update Brings the App to 2.0, Add...
CalPal Update Brings the App to 2.0, Adds Lots of New Stuff Posted by Ellis Spice on August 29th, 2014 [ permalink ] | Read more »

Price Scanner via MacPrices.net

Are We Now In The Post-Post-PC Era?
A longtime and thoroughgoing laptop aficionado, I was more than a little dismayed by Steve Jobs’s declaration back in 2010 when he sprang the iPad on an unsuspecting world. that we’d entered a “post-... Read more
Apple now offering refurbished 21-inch 1.4GHz...
The Apple Store is now offering Apple Certified Refurbished 21″ 1.4GHz iMacs for $929 including free shipping plus Apple’s standard one-year warranty. Their price is $170 off the cost of new models,... Read more
Save $50 on the 2.5GHz Mac mini, on sale for...
B&H Photo has the 2.5GHz Mac mini on sale for $549.99 including free shipping. That’s $50 off MSRP, and B&H will also include a free copy of Parallels Desktop software. NY sales tax only. Read more
Save up to $300 on an iMac with Apple refurbi...
The Apple Store has Apple Certified Refurbished iMacs available for up to $300 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free. These are the best prices on... Read more
The Rise of Phablets
Carlisle & Gallagher Consulting Group, a businesses and technology consulting firm focused solely on the financial services industry, has released an infographic depicting the convergence of... Read more
Bad Driver Database App Allows Good Drivers t...
Bad Driver Database 1.4 by Facile Group is a new iOS and Android app that lets users instantly input and see how many times a careless, reckless or just plain stupid driver has been added to the... Read more
Eddy – Cloud Music Player for iPhone/iPad Fre...
Ukraine based CapableBits announces the release of Eddy, its tiny, but smart and powerful cloud music player for iPhone and iPad that allows users to stream or download music directly from cloud... Read more
A&D Medical Launches Its WellnessConnecte...
For consumers and the healthcare providers and loved ones who care for them, A&D Medical, a leader in connected health and biometric measurement devices and services, has launched its... Read more
Anand Lal Shimpi Retires From AnandTech
Anand Lal Shimpi, whose AnandTech Website is famous for its meticulously detailed and thoroughgoing reviews and analysis, is packing it in. Lal Shimpi, who founded the tech site at age 14 in 1997,... Read more
2.5GHz Mac mini, Apple refurbished, in stock...
The Apple Store has Apple Certified Refurbished 2.5GHz Mac minis available for $509, $90 off MSRP. Apple’s one-year warranty is included, and shipping is free. Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Senior Event Manager, *Apple* Retail Market...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global event strategy. Delivering an overarching brand story; in-store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.