TweetFollow Us on Twitter

Jul 85 Letters
Volume Number:1
Issue Number:8
Column Tag:Letters

Letters

Startup Disk

David Dunham

Maitreya Design

Goleta, CA.

I'd be willing to submit a DA that changes the default drive, but you should know that the default drive has absolutely nothing to do with the start-up disk [MacTutor, June 1985, p. 24]. To change the start-up disk, you'd need to close the open system file and open a new one. This could present problems, since the application may have handles to purged resources from the system file. I don't know what happens if the file's closed from under it. What are your writer's guidelines and how much do you pay? Nothing for tips in letters, I know from experience...

[Typical pay is $100 for a column. Another $50 if you become a regular contributing editor. We hope that some things (like letter tips) people will donate for the good of the cause; we only have so much $$ to go around...-Ed.]

MicroFinder Bug Fix

Shawn Mikiten

San Antonio, Tx.

MicroFinder [June MacTutor 1-7] works well as long as you do not select a file on the other disk drive. The bug appears in the way the _Launch trap runs the application. The filename is properly passed but not the volumne the file is on. The _Launch trap will automatically attempt to run the application on the disk the MicroFinder was started from because the filename did not have the volumne specifier before it. The solution lies in the _Pack3 reply record. The variable vRefNum contains the disk drive number of the file when it returns from a successful call. Using the vRefNum value obtained, it is put in a parameter block for the File Manager call _SetVol. The parameter used is ioDrvNum. The following are directions for patching the source code so that it will work (See File Manager /OS/FS.A.1, page 26 & 33 in the new "Inside Macintosh" phone book.)

Add _SetVol trap value:

.TRAP      _SetVol               $A015

The code following _PaintRect is to be added:

_PaintRect

;   Launch Routine here

LEA          PARMBLK, A0         ;get pointer
LEA           vRefNum, A1           ; get addr. of vRefNum
MOVE.W   (A1), 22(A0)           ; put vRefNum into the
                                                               ; ioDrvNum 
parameter.
_SetVol                                            ; set it. (note A0 
points to
                                                             ; the param. 
block!)

LEA        SFileName, A1          ; get addr. of filename

Next, add the data structures necessary for the Reply record and parameter block. Add vRefNum in the Reply record:

SFREPLY:         DC.B      0,0       ; good, copy 
                 DC.B      'TYPE'    ; FType     (ostype)
 vRefNum:        DC.W       0,0      ;  vRefNum, version 
SFILENAME:       DCB.B    63,0       ; fname (string[63]) 

And now the parameter block, to be added after the WHITEPAT definition (Note that the file name pointer must be nil to force invocation of vRefNum inserted into ioDrvNum.):

;  standard 8 field parameter block for setvol.

PARMBLK:           DC.L       0            ;ioLink ptr.
                                    DC.W      0           ; ioType
                                    DC.W      0           ; ioTrap
                                    DC.W      0          ; ioCmdAddr
                                    DC.L         0          ; ioCompletion 
ptr.
                                    DC.W        0          ; ioResult
                                    DC.L          0          ; ioFileName 
ptr.
                                    DC.W        0          ; ioDrvNum

I hope this bug fix will offset the cost of the MDS software I am about to purchase. I havebeen using a friends copy and find it the easiest assembler I have used in 7 years of Apple II's, Digital 2065, IBM PC and VAX computers!

[Shawn wins the $50 for being first with his bug fix. Thank you to the four other people who submitted a fix: Loftus Becker Jr. of Hartford, CT, who submitted a similar solution to Shawn's; Tom Taylor of Provo Utah and Neal Lebedin of Palm Bay, FL., both of whom submitted similar solutions but slightly different from Shawn's; And Paul Snively of Columbus, IN. in MacAsm...-Ed.]

More Bug Fix Comments

Loftus E. Becker, Jr.

Hartford, CT.

The bug in Chris Yerga's microfinder program (ID=26) is "failure to launch". This stems from the fact that the lanuch routine will look for the named file on the default volume unless it is told otherwise. Hence, when the microfinder program is run from the default volume (usually drive 1) and tries to launch a program on drive 2, Launch gets the filename, doesn't know it's on drive 2, and tries to launch from drive 1!

Two points may be of some interest. First this is a bomb that is not trapped by Macsbug. Second, a similar bug appears in the MDS development system: If you are developing a program with the .asm, .link, and other files on the external drive, but the program itsef on the internal drive, an attempt to run it from the TRANSFER menu in the linker will produce the same error.My compliments on a magzine that has gotten better with every issue.

Alternate Bug Fix

Tom Taylor

Provo, UT

This is similar in function , but uses the stack for the parameter block...

ioVQElSize           EQU   $40     ;io param blk length
ioCompletion       EQU   $C       ;offset (ptr.)
ioVNPtr                   EQU   $12     ;offset (ptr. or nil)
ioVRefNum          EQU   $16     ;offset (word)

SUB.L    #ioVQElSize, SP    ;allocate block on stack
MOVE.L  SP, A0                        ;block ptr. to A0
CLR.L     ioCompletion(A0)  ; I always clear this
LEA         SFReply, A1             ; reply record ptr to A0
MOVE.W 6(A1), ioVRefNum(A0)  
CLR.L      ioVNPtr(A0)             ;clear name ptr.

_SetVol                                           ; go for it...
ADD.L      #ioVQElSize, SP  ; dump block

MacAsm Version of Bug Fix

Paul Snively

Columbus, IN

Apparently the standard file package, even though it automatically senses the presence of a second disk drive and, if one is present, gives you the "Drive" button in the standard dialog box, does not automatically change the default volume if the "Drive" button is hit. Where I come from, features like this are called "bugs." In other words, as far as I'm concerned, the bug is in the standard file package, not Chris' code

.

01150 *--------------------------------
01160 *        Launch Routine (MacAsm)
01170 *--------------------------------
01180          LEA     ParamBlock(PC),A0       ;File Manager paramBlock
01190          LEA     vRefNum(PC),A1          ;Volume Reference Number
01200          MOVE.W  (A1),22(A0)             ;Move to paramBlock
01210          OST     SetVol                  ;Make the default volume
01220          LEA     SFileName(PC),A1        ;Get address of file name
01230          LEA     LaunchPtr(PC),A0        ;Get address of launch 
ptr
01240          MOVE.L  A1,(A0)                 ;Move pointer to name
01250          TBX     Launch                  ;And call Launch...

Don't Like Glossy Look

Warren Michelsen

Page, Az.

I may as well comment on your new glossy look. In a word, YUCK! The gloss degrades the readability. The older stock could be viewed at any angle without glare. The older stock holds up better too; (they receive very heavy use as I refer back to them constantly). [We agree; how do you like this look? -Ed.]

Need Pascal Detective on this Bug!

Jack Cassidy

San Diego, CA.

Put a MacPascal detective on this one! The program below causes a system error (ID=02). Needless to say, I discovered this bug in a much longer program and was very confused.

program SystemBomb;
type
   count = (one, two, three, four, five);
var
   simple:array[count] of integer;

begin
    simple[five]:=31;
end.

[We'll ask our resident guru, Steve Brecher to research out this one!]

Mental Starvation of MacWorld

Rick Barrett

Dallas, TX.

AH! EUREKA,

This is the publication that I've been looking for. It's not glossy [well...-Ed.], slick, or condescending. It's meat, fact, it's wonderful! Keep up the good work...I've been rescued from the mental starvation of MacWorld.

Desperately Seeking Chief Wizard

James Muirhead

I was dissappointed to see Chris Derossi's Pascal Procedures column missing from the last issue. I was all psyched for learning window dynamics and then there was a no-show. His column is a must. Please let him know that he is sorely needed and most appreciated.

[Chris has stopped writing for reasons known only to him; perhaps your plea will awaken him...-Ed.]

MacTutor leaves me Codeless

R. Onzo

FW. Inc.

I have just recieved your complimentary issue of MacTutor and I must admit that it was an immediate sale. Your "Journal" is certainly unique compared to anything I've ever seen and the anticipation of finally being able to associate myself with a first rate tech journal leaves me almost "codeless". You've honestly made me feel like I've been trapped inside my Mac. You seemd to have just peeked inside, found me there tangled in the chips and guided me to the nearest exit showing me in the interum, the vast highways leading outward (and subsequently, inward). [Wow! we did all that? Thanks for those kind words...-Ed.]

Changing Basic Poke Codes

Terry Bartelmey

Chicago, Il.

My print routines are set up with pokes to change PRINT to LPRINT and back. I have inquired with Microsoft as to the poke locations required for the Mac, but to no avail. Could you help? [YES! See Mike Steiner's column on the structure of a Basic Program. It has all the info you need to change PRINT to LPRINT under program control.-Ed.]

Imagewrite Cutesy, but...

David Haupt

Littleton, CO.

It is cutesy to have the magazine printed out on an imagewriter but unprofessional in appearance. It is not as easy to read as a typset style woulld be. One would think that any magazine would be able to at least afford 7 grand for the Apple laser printer, wouldn't one? That would drastically increase the readability and the perceived professional level of MacTutor simultaneously.

[MacTutor is run by individuals, who, like any of us, are poor! Seven grand is seven grand, no matter if you publish a magazine or not! However, we have sacrificed the baby's milk money and now have the laser, after a three month delivery delay from Apple! How do you like it now?-Ed.]

Untested Code?

Inexcuseable is the only word for publishing untested code. Just plain sloth. Yet that is exactly what Robert Denny confesses to print [in the May issue]. I like his column on C, but I am startled at his lack of professional pride.

[ I think your letter was a little hard on us; Bob's code was taken from a much longer program that is running, but the code fragments were not re-assembled into a program just to test them specifically, hence the warning. -Ed.]

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Viber 11.9.1 - Send messages and make fr...
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
Vallum 3.3.2 - $15.00
Vallum is a little tool that helps you monitor and block apps connections and throttle apps bandwidth. It is able to intercept connections at the application layer, and hold them while you decide... Read more
Microsoft OneNote 16.31 - Free digital n...
OneNote is your very own digital notebook. With OneNote, you can capture that flash of genius, that moment of inspiration, or that list of errands that's too important to forget. Whether you're at... Read more
Apple Pages 8.2.1 - Apple's word pr...
Apple Pages is a powerful word processor that gives you everything you need to create documents that look beautiful. And read beautifully. It lets you work seamlessly between Mac and iOS devices, and... Read more
Numbers 6.2.1 - Apple's spreadsheet...
With Apple Numbers, sophisticated spreadsheets are just the start. The whole sheet is your canvas. Just add dramatic interactive charts, tables, and images that paint a revealing picture of your data... Read more
f.lux 39.9873 - Adjusts the color of you...
f.lux makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day. Ever notice how people texting at night have that eerie blue glow? Or wake... Read more
Deeper 2.5.0 - Enable hidden features in...
Deeper is a personalization utility for macOS which allows you to enable and disable the hidden functions of the Finder, Dock, QuickTime, Safari, iTunes, login window, Spotlight, and many of Apple's... Read more
NTFS 15.5.71 - Provides full read and wr...
NTFS breaks down the barriers between Windows and macOS. Paragon NTFS effectively solves the communication problems between the Mac system and NTFS. Write, edit, copy, move, delete files on NTFS... Read more
MTR 5.3.0.0 - The Mac's oldest and...
MTR (was MacTheRipper)--the Mac's oldest and smartest DVD-backup app. MTR - the complete toolbox, not a one-trick, point-and-click extractor. MTR is intended for making fair-use, backup copies of... Read more
Keynote 9.2.1 - Apple's presentatio...
Easily create gorgeous presentations with the all-new Keynote, featuring powerful yet easy-to-use tools and dazzling effects that will make you a very hard act to follow. The Theme Chooser lets you... Read more

Latest Forum Discussions

See All

Black Desert Mobile gets an official rel...
Pearl Abyss has just announced that its highly-anticipated MMO, Black Desert Mobile, will launch globally for iOS and Android on December 11th. [Read more] | Read more »
Another Eden receives new a episode, cha...
Another Eden, WFS' popular RPG, has received another update that brings new story content to the game alongside a few new heroes to discover. [Read more] | Read more »
Overdox guide - Tips and tricks for begi...
Overdox is a clever battle royale that changes things up by adding MOBA mechanics and melee combat to the mix. This new hybrid game can be quite a bit to take in at first, so we’ve put together a list of tips to help you get a leg up on the... | Read more »
Roterra Extreme - Great Escape is a pers...
Roterra Extreme – Great Escape has been described by developers Dig-It Games as a mini-sequel to their acclaimed title Roterra: Flip the Fairytale. It continues that game's tradition of messing with which way is up, tasking you with solving... | Read more »
Hearthstone: Battlegrounds open beta lau...
Remember earlier this year when auto battlers were the latest hotness? We had Auto Chess, DOTA Underlords, Chess Rush, and more all gunning for our attention. They all had their own reasons to play, but, at least from where I'm standing, most... | Read more »
The House of Da Vinci 2 gets a new gamep...
The House of Da Vinci launched all the way back in 2017. Now, developer Blue Brain Games is gearing up to deliver a second dose of The Room-inspired puzzling. Some fresh details have now emerged, alongside the game's first official trailer. [Read... | Read more »
Shoot 'em up action awaits in Battl...
BattleBrew Productions has just introduced another entry into its award winning, barrelpunk inspired, BattleSky Brigade series. Whilst its previous title BattleSky Brigade TapTap provided fans with idle town building gameplay, this time the... | Read more »
Arcade classic R-Type Dimensions EX blas...
If you're a long time fan of shmups and have been looking for something to play lately, Tozai Games may have just released an ideal game for you on iOS. R-Type Dimensions EX brings the first R-Type and its sequel to iOS devices. [Read more] | Read more »
Intense VR first-person shooter Colonicl...
Our latest VR obsession is Colonicle, an intense VR FPS, recently released on Oculus and Google Play, courtesy of From Fake Eyes and Goboogie Games. It's a pulse-pounding multiplayer shooter which should appeal to genre fanatics and newcomers alike... | Read more »
PUBG Mobile's incoming update bring...
PUGB Mobile's newest Royale Pass season they're calling Fury of the Wasteland arrives tomorrow and with it comes a fair chunk of new content to the game. We'll be seeing a new map, weapon and even a companion system. [Read more] | Read more »

Price Scanner via MacPrices.net

New 2019 16″ MacBook Pros on sale for $100 of...
Apple Authorized Reseller Adorama has new 2019 16″ MacBook Pros on sale today for $100 off Apple’s MSRP, each including free shipping. In addition, Adorama charges sales tax for NY & NJ residents... Read more
Apple Watch Series 3 GPS models on sale for l...
Amazon has Apple Watch Series 3 GPS models on sale starting at only $179. There prices are the lowest we’ve ever seen for these models from any Apple reseller. Choose Amazon as the seller rather than... Read more
iOS Bug In Facebook News Feed Lets Device Ca...
NEWS: 11.15.19- Users of the Facebook social media platform’s mobile app running on iOS devices won’t, like, this piece of news one bit in where a bug in the News Feed gave access to the camera... Read more
16″ MacBook Pros on sale! Preorder at Amazon...
Apple’s new 16″ MacBook Pros were only introduced yesterday, but Amazon is already offering a $100 discount on preorders. Prices for the base 6-Core 16″ MacBook Pros start at $2299: – 2019 16″ 2.6GHz... Read more
Use our exclusive MacBook Price Trackers to f...
Our Apple award-winning MacBook price trackers are the best place to look for the best sales & lowest prices on new and clearance MacBook Airs and MacBook Pros–including Apple’s new 16″ MacBook... Read more
New November Verizon iPhone deal: Get an iPho...
Verizon has the 64GB iPhone Xr on sale for 50% off for a limited time, plus they will include a free $200 prepaid MasterCard and a free Amazon Echo Dot. That reduces their price for the 64GB iPhone... Read more
Apple cuts prices on clearance, refurbished 2...
Apple has clearance 2018 15″ 6-Core Touch Bar MacBook Pros, Certified Refurbished, now available starting at only $1829. Each model features a new outer case, shipping is free, and an Apple 1-year... Read more
Up to $450 price drop on clearance 15″ MacBoo...
B&H Photo has dropped prices Apple’s 2019 15″ 6-Core and 8-Core MacBook Pros by $400-$450 off original MSRP, starting at $1999, with free overnight shipping available to many addresses in the US... Read more
Here’s how to save $200 on Apple’s new 16″ Ma...
Apple has released details of their Education discount associated with the new 2019 16″ 6-Core and 8-Core MacBook Pros. Take $200 off the price of the new 8-Core model (now $2599) and $200 off the 16... Read more
Price drop! 2019 15″ 2.6GHz 6-Core MacBook Pr...
Focus Camera has dropped their price for clearance 2019 15″ 2.6GHz 6-Core Space Gray MacBook Pros by $400 to $1999 shipped. Apple’s original MSRP for this model was $2399. Focus charges sales tax for... Read more

Jobs Board

Best Buy *Apple* Computing Master - Best Bu...
**746655BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Store NUmber or Department:** 002518-Atlantic Center-Store **Job Description:** Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**744973BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Store NUmber or Department:** 000949-Rochester Hills-Store **Job Description:** Read more
AV Systems Engineer at *Apple* - Theorem, L...
Job Summary Apple Retail Technology is looking for an Audio Visual Systems Engineer to design and implement scalable, next-generation A/V solutions for Apple ?s Read more
Nurse Practitioner - Field Based (San Bernard...
Nurse Practitioner - Field Based (San Bernardino, CA, Apple Valley, Hesperia) **Location:** **United States** **New** **Requisition #:** PS30312 **Post Date:** 3 Read more
Best Buy *Apple* Computing Master - Best Bu...
**746510BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Store NUmber or Department:** 001407-Milford-Store **Job Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.