[LINK] The IBM PC turns 40 today

David dlochrin at aussiebb.com.au
Sun Aug 15 11:36:38 AEST 2021

On 2021-08-14 09:14, Marghanita da Cruz wrote:
> My memory of 1982, was recommending a Northstar running CPM and Pascal to replace a Card Punch in my first job in Canberra. Learned from that about Market Power.
> Ofcourse IBM famously licensed MSDOS and the rest as they say is history.

Indeed it is!  According to Wikipedia:

> Many expected that CP/M would be the standard operating system for 16-bit computers.[64] In 1980 IBM approached Digital Research, at Bill Gates' suggestion,[65] to license a forthcoming version of CP/M for its new product, the IBM Personal Computer. Upon the failure to obtain a signed non-disclosure agreement, the talks failed, and IBM instead contracted with Microsoft to provide an operating system.[66] The resulting product, MS-DOS, soon began outselling CP/M.

(at Bill Gates' suggestion?!!) and

> A number of behaviors exhibited by Microsoft Windows are a result of backward compatibility with MS-DOS, which in turn attempted some backward compatibility with CP/M.  The drive letter and 8.3 filename conventions in MS-DOS (and early Windows versions) were originally adopted from CP/M.[75]  The wildcard matching characters used by Windows (? and *) are based on those of CP/M,[76] as are the reserved filenames used to redirect output to a printer ("PRN:"), and the console ("CON:").  The drive names A and B were used to designate the two floppy disk drives that CP/M systems typically used; when hard drives appeared they were designated C, which survived into MS-DOS as the C:\> command prompt.[77]  The control character ^Z marking the end of some text files can also be attributed to CP/M.[78] Various commands in DOS were modelled after CP/M commands, some of them even carried the same name like DIR, REN/RENAME, or TYPE (and ERA/ERASE in DR-DOS). 

Identifying peripheral devices by letter sounds to me very much like a hardware engineer's approach, compared with the hierarchical directory structure of Unix-like systems.

> Where have Control Data Corporation, Cyber76, Prime Computers, Digital Equipment Corporation, PDP11,  CSIRONET all gone?
> FORTRAN is still going strong! https://en.wikipedia.org/wiki/Fortran

If any old Fortran hands would like to try it out again, GCC Fortran is included in most Linux distributions.  It's certainly in OpenSuSE and probably also in the Microsoft Linux distribution licensed in Windows 10.

Gone is the evil "goto" in favour of if ... then ... else, it supports object-oriented design, exception conditions (Fortran 2003?), and other more advanced software engineering.

The Gnu Compiler Collection (GCC) is interesting too.  If I remember correctly, it supports many of the languages mentioned by Marghanita, including Pascal and C++, by parsing the original source code into a common pseudo-code and compiling that.

David Lochrin

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