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The Orthodox File Manager (OFM) Paradigm

by Dr Nikolai Bezroukov

Ch. 3: The History of Orthodox file Managers
First DOS and OS/2 OFMs

• Introduction
• The History of Development of Norton Commander
  • Introduction
  • The initial version of Norton Commander: NC 1.0 (1986)
  • The first upgrade: NC 2.0 (1988)
  • The most popular version of Norton Commander ever created: NC 3.0 (1989)
  • The first flip-flop: NC 4.0 (1992)
  • The last attempt to revive the brand: NC 5.0 (1993)
  • The Last of Mohicans: Norton Commander 5.5 (1998)
  • Norton Commander for OS/2
  • Notes about John Socha
• Volkov commander - a masterpiece of assembler programming
• Dos Navigator - a breakthrough in VFS development
• CN -- Connect or IBM HandShaker
• JC line -- one of the best implementations of XTree VFS in OFMs
• Other implementations
• Classic OS/2 implementations
  • File Commander (FC)
  • Other Os/2 implementations

Introduction

I am writing this chapter about semi-forgotten but very influential epoch in programming. There have always been a gifted young programmers, and there always will be. But PC revolution was a unique period that probably will never be repeated. It was a real revolution in programming despite the fact that DOS was a pretty primitive OS, actually a program loader and a couple of dozens of utilities: PC was the first computer that gave programmer unlimited time to develop their own programs as well as a large scale social activities around it in the form of PC user groups. And at the beginning the field was quite open for anybody with talent to make his/her mark: it was era of re-invention of old concepts on a new level and creation of new one, kind of programming gold rush.  Companies like Borland and Lotus were created in garages before they became large players.  A combination of qualities of the DOS and rich software landscape it created still attract people to it more then 10 years after it demise. In a way this chapter is a small contribution to the legitimizing the enormous scope of the DOS contribution to the programming art. People say that form liberates, and it looks like working with primitive OS really liberate programmers to do their best and paradoxically to a certain extent enhances not diminishes their creative abilities. And it does not surprise me that abandonware movement is going pretty strong.

Today's computers are much faster, run much more complex OSes but with Internet there is no longer social breeding ground like PC users groups anymore, places where individual programmers and groups can develop and hone their craft.  Many such groups were publishing their own newsletters which permit marketing of software by regional software developers. There is simply much less reason to drive one of two hours to such a meeting in order to see new versions of software and exchange your own software with the members of the club. Floppies were the first really democratic medium for software delivery and dramatically lowered the barrier of entry for small firms and individual programmers.  DOS application development history is a tale of raw determination, jealousy, ruthlessness, round-the-clock exhaustion, close calls, and the numerous successes and failures of the people chain which made it the most popular OS of the time. They all were and are very talented programmers being molded by the events and hardware of the times, and in this chapter I tried to reflect on that  past period (in Norton Commander story probably more then in others).  I hope that this might inspire some readers to try one or several DOS OFM managers themselves.

Due to them along with purely commercial software development shareware software development industry was quickly created.  The Association of Shareware Professionals (ASP) was formed in April 1987  and was pretty influential.

Now with Internet as the main communication medium and the ability to download anything directly made  programmers more isolated and more working in his or her bedroom or office; there is less opportunity for new ideas to spark and made a huge influence.  In a way programming is a social activity and it benefit greatly from face-to-face contacts and face-to-face discussions.

Also modern tools and libraries allow writing of pretty complex programs by even untalented/semi-talented people. As a result there is a solid layer of mediocre products on the market, making it harder for the cream to rise to the top. This is actually true for open source programming too.

The economics of programming changed too.  First PC start-ups operated in the untapped market with phenomenal growth and were run by maverick programmers who can instantly recognize the talent and were more willing to give freedom and cultivate programmers own suggestions into commercial products. Barrier of entry was also much lower then now. That's how Norton Commander was born: Peter Norton saw the potential and gave his OK for the product. In the current start-ups its much more faceless and you more need to perform a given role in a scheme defines by the founder(s); it also more about money and if start-up cannot make profit for venture investors with the initial version, it rarely get a second chance. 

DOS was one of first really affordable operating systems. Digital Research wanted $495 for CP/M-86. IBM sold PC-DOS was $40 and many software developers found it easier to port existing CP/M software to DOS than to the new version of CP/M. Since IBM's $39.95 DOS was far cheaper than anyone else's alternative everyone bought DOS. Formally the IBM PC shipped without an operating system.  IBM didn't start bundling DOS until the second generation AT/339 came out.

Until its acquisition of QDOS and development of MS DOS of its base Microsoft had been mainly a vendor of computer programming languages. It stated with BASIC interpreter: Gates and co-founder Paul Allen had written Microsoft BASIC and were selling it on disks and tape mostly to PC hobbyists.  Later they added several other languages.  But due to the tremendous success of MS DOS Microsoft became the operating systems company. As PC became the most popular personal computer, revenue from its sales fueled Microsoft's phenomenal growth, and MS-DOS was the key to company's rapid emergence as the dominant firm in the software industry. This product continued to be the largest single contributor to Microsoft's income well after it had become more famous for Windows. 

The original version of DOS (version 1.0) was released in 1981 and quickly superseded by newer versions due to phenomenal speed of development by Microsoft. For several years they produced a new version each year and each version contained significant enhancements: 

• Version 1.25, released in 1982, added support for double-sided disks, thereby eliminating the need to manually turn the disks over to access the reverse side.
• Version 2.0, released the next year, added support for directories, for IBM's then huge 10MB hard disk and for 360KB, 5.25-inch floppy disks. This was followed by version 2.11 later in the same year, which added support for foreign and extended characters.
• Version 3.0, launched in 1984, added support for 1.2MB floppy disks and 32MB hard disks. This was soon followed by version 3.1, which added support for networks.
• DOS 3.2 was probably the most popular DOS before DOS 5 was released. It was so tiny, in fact, that it can fit on a single 360K floppy disk and still leave sufficient room on the same disk for Borland C compiler and data files.

Additions and improvements in subsequent versions included support for multiple hard disk partitions, for disk compression and for larger partitions as well as an improved disk checking program, improved memory management, a disk defragmenter and an improved text editor.

In spite of its very small size and relative simplicity, it is one of the most successful operating systems that has been developed.  Paradoxically this simple system was more popular then all versions of Unix combined despite the fact that Unix is much more complex and richer OS or may be because of that.  Due to mass market created by DOS and PCs the quality of DOS applications was very high and in most cases they simply wiped the floor of their Unix counterparts. DOS has more then a dozen variant with three main: MS DOS (Microsoft), PC DOS (IBM) and DR DOS (Digital Research, the authors of DR-DOS).

DOS history outline

• 1973 Gary Kildall writes a simple operating system in his PL/M language. He calls it CP/M (Control Program/Monitor). (Control Program for Microcomputer)
• 1979
  • February Apple Computer releases DOS 3.2.
  • July Apple Computer releases DOS 3.2.1
• 1980
  • April Tim Patterson begins writing an operating system for use with Seattle Computer Products' 8086-based computer (for the new Intel 16-bit 8086 CPU).  Seattle Computer Products decides to make their own disk operating system (DOS), due to delays by Digital Research in releasing a CP/M-86 operating system. QDOS had been developed as a clone of the CP/M eight-bit operating system in order to provide compatibility with the popular business applications of the day such as WordStar and dBase. CP/M (Control Program for Microcomputers) was written by Gary Kildall of Digital Research several years earlier and was the first operating system for microcomputers in general use.
  • August QDOS 0.10 (Quick and Dirty Operating System) is shipped by Seattle Computer Products. Paterson's DOS 1.0 was approximately 4000 lines of assembler source. Although it was completed in a mere six weeks, QDOS was sufficiently different from CP/M to be considered legal. Paterson was later hired by Microsoft.  Even though it had been created in only two man-months, the DOS worked surprisingly well.  A week later, the EDLIN line editor was created.  EDLIN was supposed to last only six months, before being replaced.
  • September Tim Patterson shows Microsoft his 86-DOS, written for the 8086 chip.
  • October Microsoft's Paul Allen contacts Seattle Computer Products' Tim Patterson, asking for the rights to sell SCP's DOS to an unnamed client (IBM).  Microsoft pays less than US$100,000 for the right.
  • December Seattle Computer Products renames QDOS to 86-DOS, releasing it as version 0.3. Microsoft then bought non-exclusive rights to market 86-DOS.
• 1981
  • February MS-DOS runs for the first time on IBM's prototype microcomputer.
  • July In July 1981, Microsoft bought all rights to the DOS from Seattle Computer, and the name MS-DOS was adopted. Shortly afterward, IBM announced the Personal Computer, using as its operating system what was essentially Seattle Computer's 86-DOS 1.14. Microsoft has been continuously improving the DOS, providing version 1.24 to IBM (as IBM's version 1.1) with MS-DOS version 1.25 as the general release to all MS-DOS customers in March 1982. Now version 2.0, released in February 1983, has just been announced with IBM's new XT computer.
  • August IBM announces the IBM 5150 PC Personal Computer, featuring a 4.77-MHz Intel 8088 CPU, 64KB RAM, 40KB ROM, one 5.25-inch floppy drive, and PC-DOS 1.0 (Microsoft's MS-DOS), for US$3000. While architecturally it was largely an improved version of QDOS, IBM subjected the operating system to an extensive quality-assurance program, reportedly found well over 300 bugs, and decided to rewrite some programs. This is why PC-DOS is copyrighted by both IBM and Microsoft.
• 1982
  • May Microsoft releases MS-DOS 1.1 to IBM, for the IBM PC.  It supports 320KB double-sided floppy disk drives. Microsoft also releases MS-DOS 1.25, similar to 1.1 but for IBM-compatible computers.
• 1983
  • March MS-DOS 2.0 for PCs is announced. It was rewritten from scratch, supporting 10 MB hard drives, a tree-structured file system, and 360 KB floppy disks. October
    IBM introduces PC-DOS 2.1 with the IBM PCjr.
• 1984
  • March Microsoft releases MS-DOS 2.1 for the IBM PCjr. Microsoft releases MS-DOS 2.11.  It includes enhancements to better allow conversion into different languages and date formats.
  • August Microsoft releases MS-DOS 3.0 for PCs. It adds support for 1.2 MB floppy disks, and bigger (than 10 MB) hard disks.
  • November Microsoft releases MS-DOS 3.1. It adds support for Microsoft networks.
• 1986
  • January Microsoft releases MS-DOS 3.2. It adds support for 3.5-inch 720 KB floppy disk drives. Microsoft releases MS-DOS 3.25.
  • John Socha released Norton Commander 1.0
• 1987
  • April IBM announces DOS 3.3 for PCs, for US$120.
  • August Microsoft ships MS-DOS 3.3, the most successful version of  DOS ever.  It became de facto standard DOS in most markets quickly displacing older versions.
  • November Compaq ships MS-DOS 3.31 with support for over 32mb drives.
• 1988
  • Digital Research transforms CP/M into DR DOS.
  • June Microsoft releases MS-DOS 4.0, including a graphical/mouse interface. Dos 4.0 was not very successful.
  • July IBM ships DOS 4.0. It adds a shell menu interface and support for hard disk partitions over 32 MB.
  • November Microsoft releases MS-DOS 4.01.
• 1989
  • John Socha released Norton Commander 3.0
• 1990
  • April Microsoft introduces Russian MS-DOS 4.01 for the Soviet market. doe not have much success as DOS 3.3 was already entrenched and Pcs were weaker in comparison with Western market.
  • May Digital Research releases DR DOS 5.0.
• 1991
  • June Microsoft releases MS-DOS 5.0 which became hugely successful and gradually displace Dos 3.3 as the main DOS version. It adds a full-screen editor, undelete and unformat utilities, and task swapping. GW-BASIC is replaced with Qbasic, based on Microsoft's QuickBASIC.
  • September Digital Research Inc. releases DR DOS 6.0, for US$100.
• 1993
  • March
    Microsoft introduces the MS-DOS 6.0 Upgrade, including DoubleSpace disk compression. 1 million copies of the new and upgrade versions are sold through retail channels within the first 40 days.
  • November Microsoft releases MS-DOS 6.2.
• 1994
  • February Microsoft releases MS-DOS 6.21, removing DoubleSpace disk compression due to the lawsuit.
  • April  IBM releases PC-DOS 6.3 the first version of PC DOS significantly different from MS-DOS.
  • June Microsoft releases MS-DOS 6.22, bringing back disk compression under the name DriveSpace. This became the last version of DOS for Microsoft although its popularity never reached the levels of DOS 3.3 and DOS 5.0. It was surprisingly good and feature rich version although IBM DOS 7 was more innovative.
• 1995
  • February IBM announces PC DOS 7, with integrated data compression from Stac Electronics (Stacker).
  • April IBM releases PC DOS 7 with REXX interpreter and XEdit style editor (so called orthodox editor). Many, including myself,  consider this version to be the "Ultimate DOS".
  • September. Microsoft releases DOS 7 as a part of Windows 95. It provides support for long filenames when Windows is running, but removes a large number of utilities, some of which are on the Windows 95 CD in the \other\oldmsdos directory. (see http://www.nukesoft.co.uk/msdos/dosversions.shtml  )
• 1997. Version 7.1 was released by Microsoft. This version is part of OEM Service Release 2 and later of Windows 95. The main change is support for FAT 32 hard disks, a more efficient and robust way of storing data on large drives (see http://www.nukesoft.co.uk/msdos/dosversions.shtml  )

Although many of the features were copied from UNIX and CP/M, MS-DOS was a distinct OS that surpassed Unix in the command line interface sophistication mainly due to the standardization of  PC keyboard  and direct control of the screen.

DOS  OFM implementations were historically first and are still  important as they can be used in any DOS emulator on other operating systems like Linux.  Small is beautiful and DOS OFMs like DN, Norton Commander and Volkov Commander will forever remain the classic utilities, a powerful testament to the talent and skills of the OFM pioneers.

Of course, I am unable to review all implementations of the DOS period of OFM development, but I will try to cover the most prominent ones. We will also briefly consider OS/2 implementations with OS/2 another interesting but also extinct  OS.

The selection is somewhat subjective and biased by the value of a particular implementation to the development of the OFM paradigm. But as a rule the most important implementations were also the most popular. BTW in Eastern Europe Norton Commander interface was the standard interface for DOS, to the extent that many users would not be able to recognize regular DOS interface as a "legitimate" DOS.  As NC (2.0 and 3.0 but not 4.0) was considered to be classic by many Eastern European assembler programmers people disassembled Norton Commander to recreate libraries in order to see how it was written.  Unfortunately John Socha's famous book  Peter Norton's Assembly Language Book for the IBM PC  was not available in Russian translation at this time.

The DOS line of OFMs was the dominant line probably until 1994 or so. That changed only with the introduction of Windows 95 and Windows NT.  We will not discuss Win32 implementations (FAR, Total Commander, Norton Commander for Windows) in this chapter. They will be discussed in Chapter 5. 

Please note that some  DOS implementation migrated to Win32 (NC, DN), but some like Volkov Commander were never ported to Win32 API.