TweetFollow Us on Twitter

HFS Issues
Volume Number:2
Issue Number:7
Column Tag:Fortran's World

HFS Issues and Answers

By Mark McBride, Miami University, Oxford, Ohio, MacTutor Contributing Editor

This month's columns covers a variety of topics and issues, some of which I have come across and some which readers of MacTutor have sent in. Readers can contribute easily by sending suggestions for future column topics, bug finds, or general questions about programming the Mac in Fortran. Send all inquiries to me care of MacTutor. Now, on to the topics.

Version 2.1 and the Mac+

A more correct title for this section is Version 2.1 and HFS. As reported in MacTutor (Vol. 2 No. 5 May 86), Microsoft Version 2.1 does not work with HFS. [See Microsoft's reply in the box at the end of this article. -Ed] The compiler eventually gets lost in locating its files, even when all files are on the desktop and no folders reside on the disk. But do not completely despair, because you can run V2.1 on the Mac+ and on a rom upgraded 512k Mac if you use MFS under Finder 4.1.

To convince myself of this, I conducted a test of V2.1 on several machine configurations. I used four different machine configurations. Table 1 summarizes the results. In the following configurations, MFS system refers to MFS formatted diskettes with the old system (pre-Version 3.0) and Finder 4.1, while HFS system refers to HFS formatted diskettes with the new system (Version 3.1.1) and Finder 5.2. All tests were conducted with MS Fortran Version 2.1.

Configuration A was a 512k Mac with the rom upgrade and a two disk (400k each) MFS system. Configuration B was a 512k Mac with the rom upgrade and a one disk (800k) MFS system. Configuration C was a Mac+ with a one disk (800k) MFS system. Finally, configuration D was a 512K Mac with the rom upgrade and a one disk (800k) HFS system.

In case the reader was wondering how an 800k MFS system was created, here are the steps necessary (This tip was passed to me by Absoft tech support. Absoft tech support hadn't tried this, but it was suggested to them by another user):

800k MFS Diskette

1. Initialize an 800k diskette with the new system (3.1.1) under Finder 5.2.

2. Boot a system disk with the old system and Finder 4.1.

3. Eject the old system disk and insert the initialized 800k diskette in the 800k internal drive.

4. Choose 'Erase' from the 'Special' menu of Finder 4.1.

5. Move the old system, Finder 4.1, MS Fortran, and all other files onto the 800k MFS diskette, then reboot. You now have an 800k MFS system for use on a 512k Mac with the rom upgrade or on a Mac+.

In addition to trying four different machine configurations, I also tried three different types of programs. The first program was the Shell program presented in MacTutor (Vol. 1 No. 12, November 1985). This program uses several toolbox routines and has an event loop structure. The second program was an old Probit regression program I transferred down from the mainframe. The code structure is sequential from start to stop. The reason for picking this program was that the program opens a data file on a disk using a hard-coded 'diskname:filename' in the source, i.e.,

open(25,status="KEEP",file="Probit.Data")

[Note: The standard JCL used on mainframes to link a Fortran file number with a physical device does not exist on the Mac. Instead, that association is done directly in the Fortran code with an open statement. -Ed]

The third program was the Probit regression program modified to use the 'stdfil' subroutine (see MacTutor Vol. 2 No. 2, Feb. 86) to get the data file name to open on the disk, i.e.,

ok=stdfil(1,'',fname,1,'TEXT')
if (ok) then
  open(25,status="KEEP",file=fname)
else 
  goto 13
endif

The reason for doing this was to check for the ability to run the resulting compiled and linked application under MFS or HFS using the standard getfile and putfile routines as used by 'stdfil', with the new ROMS!

As shown in Table 1, each combination of program and machine configuration is tested for compiling/linking, running under MFS, and running under HFS. The 'running under HFS' category meant that the fully compiled and linked program was moved over to an 800k HFS system and run under System 3.1.1 and Finder 5.2

As can be seen from Table 1, Version 2.1 will run under MFS, even on a Mac+ or rom upgraded 512k Mac as long as you stay with MFS. The major exception to this statement is that unmodified use of the MS Fortran supplied subroutine 'stdfil' will not work under MFS with the new roms. If the program requires a datafile name during execution, you can either prompt the user for the name using an input routine of your own design or attempt to modify 'stdfil' so it works with the new roms. Hopefully, all of this will be history by the end of summer with the release of Version 2.2, which has HFS compability. [Other apparent problems are you can't have more than three files opened at once or more than two files if you use the default printer file. This can be corrected by setting the linker z option for more heap space, or declaring a large array in a dummy subroutine. Also, the full listing option inserts a funny page control character that causes the imagewriter to go beserk ejecting pages, and hangs the Mac, when printing from Edit. So you can't print the full listing file, except from the compiler print option. -Ed.]

Debugging Event Loops

The source code debugger is one of the most useful features of MS Fortran. On many occasions, this debugger has saved me considerable time in locating a program bug. Eventually, as you develop Fortran programs using the Mac user interface, you will need to debug an event loop. If you try single stepping through the program, however, you will find that you cannot debug the event loop. This happens because the debugger has its own event loop and is processing all events. There is a simple and easy way around this 'apparent' problem.

The debugger has two types of breakpoints: soft and hard. A soft break point is set by moving the cursor (the left pointing arrow) to the source statement where you want to set the soft breakpoint. Once you set the soft breakpoint, then you can hit 'return' which executes all statements from the current statement (indicated by the rectangle box) up to and including the soft break point statement; or you can type 'command-g' which executes all statements from the current statement up to and not including the soft break point. A hard break point is set by clicking the number of the statement to be stopped at. Generally, in the process of locating the statement for which a hard breakpoint is to be set the soft breakpoint cursor also moves. Issuing the home cursor command (command-h) returns the soft breakpoint to the current statement. After setting the hard breakpoint(s), the proceed to breakpoint command (command-x) executes the program up to but not including the hard breakpoint statement. If you wish to stop at that same breakpoint again, always single step through the statement for which the breakpoint is set. This is necessary because the debugger clears any breakpoint set on the current statement when command-x is pressed.

Whenever you set a soft or hard breakpoint the debugger executes a send-behind on all its windows and effectively 'hides' itself until the breakpoint is encountered. Thus, by setting a hard break point at the call to the routine you are interested inside the event loop, you can get full processing of your event loop until you get to the breakpoint. When the breakpoint is encountered, the debugger issues a bring to front for the source code window and you are back in the full debugger.

By using soft and hard breakpoints, you can achieve several goals from within the debugger. Figure 1 illustrates the setting of a soft breakpoint near the start of the program to remove the default window MS Fortran creates. By setting the soft breakpoint after the call to FRONTWINDOW and CLOSEWINDOW and then pressing 'return' the default window is removed without bombing the debugger. Figure 2 shows the result of this process.

Figure 3 illustrates setting a hard break point within the menus subroutine of a typical event loop. Notice that the hard breakpoint is set after the call to MENUSELECT. If the hard breakpoint had been set for MENUSELECT statement, then you would be unable to track the mouse within the menus. Figure 4 shows the program running, with the debugger in the background, after issuing the execute to breakpoint command. Finally, Figure 5 illustrates the return of the debugger when the hard break point is encountered with the variable window showing which menu item had been selected. The variable window indicates that the second menu item of the Options menu (ID=32) had been selected, leading to the breakpoint.

Is handling of menu related events during debugging altered by the presence of the debugger menu? Surprisingly, and convienently, no. When the debugger is in the background and your menus have ID's different than 5, then there will be no problem. Judicious use of hard and soft breakpoints, particularly within event loops, can speed program development considerably.

Reader's Questions and Tips

Q: A letter from Edward Groth of Scottsdale, AZ arrived the other day. The two listings he included are reprinted as Listing 1 and 2. As can be seen, both concern problems with large arrays (approx. 90,000 elements). As Mr. Groth correctly states in the listings, the programs don't work on the 512k Mac with version 2.1, but do work under Absoft version 2.0b (the predecessor to version 2.1).

A: After conversations with Absoft technical support (who have always been helpful), the reason for the two programs not working was found: a serious bug in the compiled code which could potentially affect any array which takes up more than 32k of space. The bug does not always show up. For example, if Listing 1 is run under Version 2.1 on the Mac+, it works fine; as will Listing 2 if all integer declarations are integer*4 instead of integer*2. Again, however, Absoft tech support stated that the bug could occur for any array (real or integer) which occupies more than 32k of space. So if you are using large arrays, watch out.

I inquired about a work around or patch. There is no work around for this bug. Absoft said a patch would not be forthcoming unless the release of Version 2.2 is significantly delayed since 2.2 does not contain this bug (my beta-test copy of Version 2.2 ran both programs properly! ). As to why version 2.0b correctly handles Listings 1 and 2, but 2.1 does not, the core compiler routines which deal with arrays were completely rewritten between the two versions to improve performance [In other words, it's a new product! -Ed.]

Q: Mr. Groth asked a second question relating to the sequence of compile, link, Rmaker. The bottom of page 2 of the Rmaker manual supplied with MS Fortran states that Rmaker only works with resource sizes of 32k or less. Well, if you have to link the runtime before you add the resources with Rmaker (since the MS Fortran linker only understands output from the compiler), then it appears that only applications of size 32k or smaller can be created as a standalone application with resources added.

A: The limitation on Rmaker is due to a bug in the 64k roms (not the new 128k roms). Apple Tech Note #63 contains the full details (the Apple Tech Notes can be found on Compuserve's Mac Developer Maug, DL8). Evidently, bit 15 in the size of the resource is handled improperly causing any resource whose size has bit 15 set would be written by WriteResource as having size 0. Thus resources of size 0-32k can be written, 32k-64k can't, 64k-96k can, etc. If your application uses the toolbox routines WriteResource or GetHandleSize, you may want to look at Apple Tech Note #64 which gives a work around for the problem.

Tech Note #64 solves the problem for an application that uses WriteResource with the 64k roms, but does not solve the problem for using Rmaker and a compiled, linked Fortran application. However, a solution is straight forward. Instead of including the compiled, linked code using the include statement, append the new resources to the compiled, linked application. For example:

instead of:

Hilbert
APPLFORT

include: hilbert apl

.... (your resources)

use:

!hilbert apl
APPLFORT

.... (your resources)

This second approach also can be used to add resources to an unlinked application you are still debugging. By setting the 'APPLFORT' tags, the debugger will still recognize the compiled code.

Tip: Mr. Bob Andris of Saratoga CA writes in with a tip for attaching assembly language to your Fortran programs. If the assembly subroutine is compiled under the MDS, there is a simple and elegant way of getting the subroutine into the form that the Fortran linker wants. In the MDS Linker file, make the Output file name 'abcdef.sub' and then add a line you wouldn't normally have in an application's Linker File, namely '/Data'. The Linking and Mapping then produce a 'psuedo' application that is just the compressed DATA application you need. Just link it in with the Fortran linker. For example:

f YourProg
f abcdef.sub
l f77.rl
o YourProg

Thanks, Bob.

Q: Mr. Jim Bishara of Metairie, LA inquires as to whether there is an equivalent statement to the basic command FRE(-1).

A: The basic FRE(-1) command returns the number of bytes of available space on the Macintosh heap with MS Basic. The following code compacts the current heap zone, purges all purgeable blocks from the zone, then returns the number of available bytes in the largest contiguous free block in the zone. Be forewarned though, that all the space is unlikely to be available since some resources may be read back into memory the next time they are needed.

include memory.inc
integer*4 Grow

Grow=100

Grow=toolbx(MAXMEM,Grow)

After execution of the toolbox routine, Grow will contain the number of available bytes in the large contiguous free block. This probably is preferable to using FREEMEM, since FREEMEM counts all available bytes, whether contiguous or not. If the are any non-relocateable blocks in the heap, then not all the memory returned by FREEMEM will be available.

Other letters have inlcuded more tips, questions, and suggestions for future topics. Please keep the letters coming and I'll try to cover as many of the topics/issues as I can in future columns. Next month's column will cover using the print manager, pictures, and the deskscrap all in one graphing application! Till then, happy computing.

Listing 1

 program MEMTEST
 
 implicit none
 integer z,zsize,i,j
 virtual z(0:300,0:300)
 
 type "Array Size?  ";accept zsize
 
 do (j=0,zsize)
   do (i=0,zsize)
     z(i,j)=i*(zsize+1)+j
   repeat
 repeat
 
 write(9,*) 'Upper Left Corner  ',z(0,0)
 write(9,*) 'Upper Right Corner ',z(zsize,0)
 write(9,*) 'Lower Left Corner  ',z(0,zsize)
 write(9,*) 'Lower Right Corner ',z(zsize,zsize)
 write(9,*) 'Finished'
 
 pause
 end

*  This works right in Absoft V2.0b but gives incorrect values 
*  in MS V2.1 for the upper left and lower left corners when 
*  zsize is 219 or greater.

Listing 2

 program MEMTEST
 
 implicit none
 
 integer*2 z,zsize,i,j
 dimension z(0:400,0:400)
 
 type "Array Size?  ";accept zsize
 
 do (i=0,zsize)
   do (j=0,zsize)
     z(i,j)=i+j
   repeat
 repeat
 write(9,*) 'Finished'
 
 pause
 end
 
*  Listing 2 works OK with zsize of 218 or less.  With zsize 
*  (array size) of 219 or larger up to and including 300, the 
*  system crashes with the dreaded black bomb or worse yet, it
*  completely hangs after trying to destroy the machine. Try 
*  about 280.  This works fine in Absoft V2.0b for all values of
*  zsize<=300.  Obviously it should work on a 512k Mac but
*  does not do so under the official 2.1 MS Fortran.

Table 1

Machine Configuration

A B C D

Shell Program

compile/link yes yes yes no

run under MFS yes yes yes n/a

run under HFS yes yes yes n/a

Probit Version 1

compile/link yes yes yes no

run under MFS yes yes yes n/a

run under HFS no no no n/a

Probit Version (stdfil)

compile/link yes yes yes no

run under MFS no no no n/a

run under HFS no no no n/a

Configuration A: A 512k Mac, with rom upgrade, using two 400k disks with the MFS system.

Configuration B: A 512k Mac, with rom upgrade, using one 800k disk with the MFS system.

Configuration C: A Mac+ using one 800k disk with the MFS system.

Configuration D: A 512k Mac, with rom upgrade, using one 800k disk with the HFS system.

Microsoft Responds

This is in response to the May issue's complaint about Microsoft Fortran for the Macintosh. Microsoft is committed to making Fortran, as is the case with all our products, the best it can be. We appreciate MacTutor's criticisms, and are taking to heart all suggestions for improving the product.

Microsoft has received the first installment of the next version of Fortran from Absoft. Since then, we have been putting it through extensive internal and outside testing, and Absoft has characteristically been doing an excellent job of fixing bugs and implementing changes recommended by the testers. What will result from our thorough quality control process is another version of Macintosh Fortran that will best meet the user's needs.

We wish we could announce a release date, but that would be a disservice. Our philosophy is to work hard and release great products. One cannot accurately predict what changes will be necessary until after the testing is complete, and we will not release a product that is anything but the best quality. This next release and its timeliness, however, are a top priority. When available, it will have additional useful features as well as making full use of your new machines.

We want to straighten out one inaccuracy in the May Fortran column; Version 2.1 does work on the Mac Plus. You must use the old versions of System and Finder 4.1 on the Fortran disk. You cannot be using HFS folders.

- Ray Bily, Product Manager, Apple Languages, Microsoft Corp.

 
AAPL
$102.50
Apple Inc.
+0.00
MSFT
$45.43
Microsoft Corpora
+0.00
GOOG
$571.60
Google Inc.
+0.00

MacTech Search:
Community Search:

Software Updates via MacUpdate

Mac DVDRipper Pro 5.0 - Copy, backup, an...
Mac DVDRipper Pro is the DVD backup solution that lets you protect your DVDs from scratches, save your batteries by reading your movies from your hard disk, manage your collection with just a few... Read more
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

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
PC Outlook Improves, But 2014 Shipments Still...
According to the International Data Corporation (IDC) Worldwide Quarterly PC Tracker, worldwide PC shipments are expected to fall by -3.7 percent in 2014. To hat’s actually an improvement from the... Read more
IDC Lowers Tablet Sales Projections for 2014...
Following a second consecutive quarter of softer than expected demand, International Data Corporation (IDC) has lowered its worldwide tablet plus 2-in-1 forecast for 2014 to 233.1 million units. The... 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

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.