TweetFollow Us on Twitter

Sep 86 Letters
Volume Number:2
Issue Number:9
Column Tag:Letters

Letters

Fortran Bugs

Jim Bishara

New Orleans

Help, Help, I can't get SetItemStyle toolbox call to work. I've spent at least 40 hours reading the Microsoft Fortran manual and no luck. I'm running a Mac Plus under Finder 4.1 (dumb Microsoft), with version 2.1. I used the DEMO.INC file supplied with the Fortran. When it tries to execute the trap, a bomb message returns ID=02. What can be wrong?

call toolbx(GetItemStyle, menuhandle, itemcount, chstyle) {works fine}

call toolbx(SetItemStyle,menuhandle,itemcount, chstyle) {bombs like a champ with ID 02}

[Probably the toolbx.par file is wrong. We've found lots of errors in it in the past. SetItemStyle probably is not a VAR. Just a guess. -Ed]

Aztec C 1.06H Release

Don McCauley

Ridgecrest, CA

I purchased my Aztec C from ComputerWare, a MacTutor advertiser, and on May 20, I received a beta release of version 1.06H, created May 12th. This time I received tens of pages of update documentation from their new manual, fresh off the press. Included with this update is an index. Unfortunately, the index seldom includes the key words I've looked for. For example, try to find in the index where to find how many characters are significant in a variable declaration? I've had trouble with multiple defined symbols using "theWindow" from Takatsuka's book Using the Macintosh Toolbox with C, page 70. Struct assignments in SetRects don't seem to work right for me. Any help for us Aztec'ers in the ABC's of C column? As far as HFS goes, basically it's "so far, so good" with this version. I really love the Manx UNIX like vi editor, Z. Manx is worth it just for z. I'm excited about C as a language and more specifically, about Aztec C for my Mac Plus.

[I'm sorry to report that Bob Gordon, our ABC's of C author, became seriously ill this month and has been unable to work on his C column for some time. We've talked to him and he reports he is beginning to recover and hopes to contribute another ABC article next month. We wish Bob a speedy recovery as I'm sure all our C fans do. A few notes and letters to Bob would be most appreciated I'm sure. Send them to Bob care of MacTutor and we will forward them on. -Ed.]

What's Wrong with this Picture?

move.l  #4, D0
_NewHandle
LEA   #$40E132,A1  ;get icon pointer in rom
move.l  A1, (A0) ;save pointer in new handle
 pea  top(A5)  ;set up rom call
move.l  A0, -(SP)  ;handle to icon
_PlotIcon ; plot it

[Note: I tried to write an assembly routine to plot the famous stolen icon from ROM memory, but it didn't work. -Ed.]

Icon Problem Above

Lon Kelly

College, AK

Thank you for your recent letter regarding the stolen icon problem. The simple explanation for the failure is that the line

LEA #$A0E132, A1

is not a legal 68000 assembler statement. This is because LEA will not use the immediate mode for the effective address field: only control addressing modes are allowable (see Morotola's Programmer's Reference Manual, p. 102 and p. 53). However, Mac C will assemble the line, setting the effective address bits as though it were a MOVE instruction. The linker listing shows the code actually generated:

Mac C Linker Listing:

4: 43 FC 00 40 E1 32    lea   #$40E132, A1
A: 20 89  move.l a1, (a0)
C: 48 6D FF  FC  pea top(a5)

Note that the first six bits indicate the effective address mode. Mac Nosy version 2.1 will disassemble the errant code without comment, as shown by the Nosy listing, but it loses track of 2 bytes and the next instruction:

Nosy output:

4: 43FC 0040 E132  LEA  #$40E1232,A1
; where did location A go?
C: 486D FFFC     PEA glob1(A5)

The Mac Zap listing shows that the code is actually on the disk as in the linker listing and that Nosy just got confused. It is interesting that Mac Zap and TMON, which have relatively simple disassemblers, recognize the illegality, while the assembler and Nosy do not.

Mac Zap Disassembly:

00F3C4  43FC   DC.W $43FC  ;illegal 

I believe you have another, more insideous problem doe to direct manipulation of "master pointers" created by _NewHandle. You seem to simply write over them. This leaves the memory manager with a master pointer pointing to ROM or to part of your code, rather than to a "relocatable block". I've never done this, but I sure expect it would cause problems with heap compaction, etc. What will happen if you call _DisposeHandle for a "handle" to ROM?

I think it would be a lot safer to do something like this: first make a constant pointer in your code, then push it's address (which would be a handle in the sense of a pointer to a pointer, but not in the context of the memory manager) as a parameter to _PlotIcon. See the untested suggestion below:

romicon:  dc.l   $40E132
 pea  top(a5)
 pea  romicon
 _PlotIcon

More on the Icon Problem

Peter Brown

La Mirada, CA

Thank you for your response to my letter. I have to admit my surprise at receiving it. You must be swamped wiath mail and I really appreciate your taking time out to write.

I took a look at the code you sent me and the stolen mac icon problem in particular. I banged in the whole listing as it stood and then fiddled around with it. The problem looked like this: the "LEA" instruction does not require use of the immediate mode designator, '#'. If it wasn't just a handwriting boo-boo, I'm surprised your assembler took the statement. [See previous letter. -Ed] This is possible pitfall #1. Well, to test things out using TMON, I inserted an:

LEA $40AD40, A1 ; NOTE FOR OLD ROMS

instruction at the spot in question, set the program counter to the beginning of ICONSTUFF: and let 'er rip (an instruction at a time). Lo and behold, I got a bunch of barbage in the output icon.

I then thought I'd trace through the ROM code to see what it looked like. The routine itself is pretty compact and straight forward, and no special handling of address registers. After a few different efforts, including getting garbage plotted from the icon data in RAM, I realized that the LEA 'ROM' location, A1 instruction assembled as 6 bytes, not 4 as with the LEA ICON, A1 which uses program counter relative addressing. I was coding over the next instruction! This is possible pitfall #2.

After re-assembling the file with the LEA $40AD40, A1 in place, (and no typos!), the code worked! Best of luck and keep up the great work with MacTutor.

 lea  icon, a1 ;assembles in 4 bytes 
 move.l a1, (a0) ;move pointer to a0 h
 pea   top(a5) ;push rect
 move.l a0, -(SP);push handle
 _PlotIcon;plot icon

[The advantage of being Editor of MacTutor, is that I have 6,000 "registered" programmers to call on for assistance! Thanks guys! -Ed]

Loves TML

Micahael Rollins

Broken Arrow, OK

I appreciate all the help your publication has provided over the last few months. There is nothing better than good examples to help learn a system as sophisticated as the Mac's. Since I have started using MacTutor and programming with TML's Pascal, I have managed to come a long way up the learning curve on the Mac. I find that I turn frequently to Mactutor for help with ROM calls and Resource Files that are not well explained in Inside Macintosh. I looke forward to each month's copy. Keep up the good work.

Tutor and TML Great

Terry Permeuter

Seattle, WA

Just got the TML Pascal compiler and saw an issue of MacTutor. Both look great! Enclosed is my check for a year's subscription. If you haven't done so yet, could you plan on an article or two on the differences between MacPascal and TML? The ads say TML compiles MacPascal programs, but I've already found some walls when trying that. A short guide on what to look for would be helpful! Keep up the good work!

[MacPascal is so non-standard that it is a dis-service to try and maintain compatibility with it. See the new LightSpeed Pascal, which IS TML compatible. -Ed]

Thanks for the Review

Dan Weston

Famous Assembly Author

I hope that by now you have received a final manuscript copy of volume two of the Complete Book of Macintosh Assembly Language Programming that you so thoroughly reviewed at the mid-way point. I was able to incorporate many of your suggestions into the final version, but not all. In particular, I didn't write anything about AppleTalk because I haven't ever had the opportunity to use it in any real situation. I think the strength of my books is that they are derived from my experience as a software developer, so I am reluctant to write about things that I have no direct experience with. Also, AppleTalk seems to be worth an entire book all by itself. I am very grateful for the comments that you made however, because I think they helped me produce a better book in the end.

I don't know exactly when we will go into final editing, but I assume that it will begin July sometime. I expect the final book out sometime in November. Thanks for the nice words in MacTutor on my new books!

Language Fanatic

David Adamski

Tulsa, OK

Well, I see by the EXP 5/1/86 notcie on my mailing label that it's time to renew my subscription to MacTutor. Enclosed please find my personal check for $30. MacTutor is one programming journal that I would NOT want to be without. Although I subscribe to a variety of computer publications, I look forward to receiving yours each month. As a language fanatic I feel that MacTutor is by far the most informative Journal, with regular articles on all the popular programming languages for the Mac. Sorry to hear about your robbery, hope my renewal helps you get back on track. Keep up the good work, and I wish you luck in the future. [MacTutor is enjoying great success this summer, thank you. -Ed.]

Questions

Bill Westcott

San Leandro

I got an idea! I've been trying to learn TML Pascal and Mac programming at the same time and your magazine has been a great help, but when my programs don't work, it's sort of like playing Zork. I keep trying everything till it works. Very time consuming. I noticed a green "3" sticker on one of my last MacTutor issues. That means that there are at least ten people in my three digit zip code who subscribe to your magazine. What do you think of a "Mac.Guru" program where people who know what they're doing might volunteer to answer stupid questions and your organization could somehow bring them together with askers of stupid questions? Just thought I'd ask. [Here's a stupid question: How would you do that? -Ed]

How do others do it?

J.M. Puckett

Austin, Tx

Oh No! I just received my April issue of MacTutor and on my label I see that my subscription is due to run out beginning of next month. So enclosed herein is a check for $30. Also I would like to know if you could send me an author's kit. I have just completed a series of desk accessories and applications using Megamax C, and am anxious to share some of the neat things I have found.

Yours is an excellent publication. I have learned a lot from it. However, I would like to submit a suggestion: Please suggest that some of your experts write articles on defining one's own menu, window, and control definitions. I have been attempting to write these kind of programming objects, and have had, for the most part, great success just by following the hints in Inside Macintosh; but I would sure like to see how others are creating such things. [Keep watching my Intermediate Mac'ing column especially last month's TML shell program. It had a lot of goodies! -Ed]

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Lyn 1.8.5 - Lightweight image browser an...
Lyn is a fast, lightweight image browser and viewer designed for photographers, graphic artists, and Web designers. Featuring an extremely versatile and aesthetically pleasing interface, it delivers... Read more
Apple iOS 10.2.1 - The latest version of...
iOS 10 is the biggest release of iOS ever. A massive update to Messages brings the power of the App Store to your conversations and makes messaging more personal than ever. Find your route with... Read more
Apple Security Update 2016-003 Supplemen...
Apple Security Update is recommended for all users and improves the security of OS X. For detailed information about the security content of this update, please visit: http://support.apple.com/kb/... Read more
Apple macOS Sierra 10.12.3 - The latest...
With Apple macOS Sierra, Siri makes its debut on Mac, with new features designed just for the desktop. Your Mac works with iCloud and your Apple devices in smart new ways, and intelligent... Read more
BetterTouchTool 1.992 - Customize Multi-...
BetterTouchTool adds many new, fully customizable gestures to the Magic Mouse, Multi-Touch MacBook trackpad, and Magic Trackpad. These gestures are customizable: Magic Mouse: Pinch in / out (zoom... Read more
Viber 6.5.5 - Send messages and make cal...
Viber lets you send free messages and make free calls to other Viber users, on any device and network, in any country! Viber syncs your contacts, messages and call history with your mobile device, so... Read more
Opera 42.0.2393.137 - High-performance W...
Opera is a fast and secure browser trusted by millions of users. With the intuitive interface, Speed Dial and visual bookmarks for organizing favorite sites, news feature with fresh, relevant content... Read more
iClock Pro 3.4.7 - Customize your menuba...
iClock Pro is a menu bar replacement clock for Apple's default clock. iClock Pro is an update, total rewrite and improvement to the popular iClock. Have the day, date and time in different fonts and... Read more
PhotoDesk 4.1.5 - Instagram client for p...
PhotoDesk lets you view, like, comment, and download Instagram pictures/videos. (NO Uploads! / Image Posting! Instagram forbids that! AND you need an existing Instagram account). But you can do so... Read more
Capo 3.5.1 - Slow down and learn to play...
Capo lets you slow down your favorite songs so you can hear the notes and learn how they are played. With Capo, you can quickly tab out your songs atop a highly-detailed OpenCL-powered spectrogram... Read more

Clash Royale gets some serious balance u...
| Read more »
Ironhide Game Studio prepares for a busy...
Kingdom Rush breathed fresh life into the tired tower defense genre way back in 2012. The game was a robust challenge that somehow managed to lift you up, rather than leaving you feeling crushed and hopeless. The rich array of unit types and... | Read more »
Collect pets and sling arrows in Arcane...
Mobile gaming is a crowded market, but regular updates are a good way to keep us attention-short players keen. The brand new content in Arcane Online is a prime example. Published by Japanese developer Gala, Arcane Online is a fantasy MMO that... | Read more »
Super Mario Run dashes onto Android in M...
Super Mario Run was one of the biggest mobile launches in 2016 before it was met with a lukewarm response by many. While the game itself plays a treat, it's pretty hard to swallow the steep price for the full game. With that said, Android users... | Read more »
WarFriends Beginner's Guide: How to...
Chillingo's new game, WarFriends, is finally available world wide, and so far it's a refreshing change from common mobile game trends. The game's a mix of tower defense, third person shooter, and collectible card game. There's a lot to unpack here... | Read more »
Super Gridland (Entertainment)
Super Gridland 1.0 Device: iOS Universal Category: Entertainment Price: $1.99, Version: 1.0 (iTunes) Description: Match. Build. Survive. "exquisitely tuned" - Rock Paper Shotgun No in-app purches, and no ads! | Read more »
Red's Kingdom (Games)
Red's Kingdom 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Mad King Mac has kidnapped your father and stolen your golden nut! Solve puzzles and battle goons as you explore and battle your... | Read more »
Turbo League Guide: How to tame the cont...
| Read more »
Fire Emblem: Heroes coming to Google Pla...
Nintendo gave us our first look at Fire Emblem: Heroes, the upcoming mobile Fire Emblem game the company hinted at last year. Revealed at the Fire Emblem Direct event held today, the game will condense the series' tactical RPG combat into bite-... | Read more »
ReSlice (Music)
ReSlice 1.0 Device: iOS Universal Category: Music Price: $9.99, Version: 1.0 (iTunes) Description: Audio Slice Machine Slice your audio samples with ReSlice and create flexible musical atoms which can be triggered by MIDI notes or... | Read more »

Price Scanner via MacPrices.net

Deal alert! 13-inch 2.0GHz MacBook Pros for $...
B&H Photo has the new 2016 13″ 2.0GHz non-Touch Bar MacBook Pros in stock today and on sale for $225 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 2.0GHz MacBook Pro... Read more
Free LibreOffice Portable 5.2.4 Complete Offi...
PortableApps.com and The Document Foundation have announce the release of LibreOffice Portable 5.2.4. LibreOffice Portable is an Open Source full-featured office suite — including a word processor,... Read more
Apple Planning Three New Tablets For 2017 – D...
Digitimes’ Rebecca Kuo and Joseph Tsai say that unnamed insider sources report Apple having three new tablets in the pipeline for 2017 release: a 9.7-inch model with a friendly price range, a new mid... Read more
Roundup of 15-inch Touch Bar MacBook Pro sale...
B&H Photo has the new 2016 15″ Apple Touch Bar MacBook Pros in stock today and on sale for up to $150 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 15″ 2.7GHz Touch Bar... Read more
Apple refurbished iPad Pros available for up...
Apple has Certified Refurbished 9″ and 12″ Apple iPad Pros available for up to $160 off the cost of new iPads. An Apple one-year warranty is included with each model, and shipping is free: - 32GB 9″... Read more
16GB iPad Air 2, Apple refurbished, available...
Apple has Certified Refurbished 16GB iPad Air 2s available for $319 including free shipping. A standard Apple one-year is included. Their price is $60 off original MSRP for this model. Read more
Apple iMacs on sale for up to $120 off MSRP
B&H Photo has 21″ and 27″ Apple iMacs on sale for up to $120 off MSRP, each including free shipping plus NY sales tax only: - 27″ 3.3GHz iMac 5K: $2199 $100 off MSRP - 27″ 3.2GHz/1TB Fusion iMac... Read more
Apple refurbished Apple TVs available for up...
Apple has Certified Refurbished 32GB and 64GB Apple TVs available for up to $30 off the cost of new models. Apple’s standard one-year warranty is included with each model, and shipping is free: -... Read more
Save up to $350 with Apple Certified Refurbis...
Apple has Certified Refurbished 2015 21″ & 27″ iMacs available for up to $350 off MSRP. Apple’s one-year warranty is standard, and shipping is free. The following models are available: - 21″ 3.... Read more
2015 12-inch Retina MacBooks, Apple refurbish...
Apple has Certified Refurbished 2015 12″ Retina MacBooks available for up to $410 off original MSRP. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The... Read more

Jobs Board

*Apple* & PC Desktop Support Technician...
Apple & PC Desktop Support Technician job in Manhattan, NY Introduction: We have immediate job openings for several Desktop Support Technicians with one of our most Read more
*Apple* & PC Desktop Support Technician...
Apple & PC Desktop Support Technician job in Stamford, CT We have immediate job openings for several Desktop Support Technicians with one of our most well-known Read more
*Apple* Retail - Multiple Positions - Apple,...
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* Site Security Manager - Apple (Unite...
# Apple Site Security Manager Job Number: 54692472 Culver City, California, United States Posted: Jan. 19, 2017 Weekly Hours: 40.00 **Job Summary** The Apple Read more
*Apple* macOS Systems Integration Administra...
…most exceptional support available in the industry. SCI is seeking an Junior Apple macOS systems integration administrator that will be responsible for providing Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.