Tuesday, 10 April 2018

Windows File Manager

The Windows File Manager was the file manager included with Microsoft Windows starting with version 3.0 until Windows 95 and NT where it was phased out in favour of Windows Explorer. The Windows File Manager was used to perform file management and hence replaced the functionality of MS-DOS (earlier versions of Windows had a simple file manager called MS-DOS Executive).

Why are we talking about File Manager? Well an updated version has been released that will work on Windows 10! You can download it here if that kind of thing floats your boat.

Thursday, 5 April 2018

SNOBOL (StriNg Oriented and symBOlic Language)

SNOBOL does seem at first glance a typo of a more familiar sounding programming languages like COBOL but is in fact SNOBOL a series of languages developed at Bell Laboratories by David J. Farber, Ralph E. Griswold and Ivan P. Polonsky in the early 1960s. SNOBOL was designed for text processing and pattern matching and was quite different to most other programming languages of the time.

SNOBOL was originally developed for the symbolic manipulation of polynomials on the IBM 7090 mainframe in 1962 but the language became popular and was refined and expanded culminating in SNOBOL4 in 1967.

SNOBOL4 was based on a virtual machine which meant it was much more portable. The language was popular in teaching, artificial intelligence and text manipulation in the 1970s and 1980s though it has been eclipsed by newer tools and languages.

More recently derived languages like SL5 and Icon have added structured language concepts to SNOBOL (which has none itself).

So how do you do a "Hello World" program in SNOBOL?

OUTPUT = "Hello world" 
END

Sunday, 1 April 2018

The story behind Apple DOS

This is a fascinating article on the Apple's first Disk Operation System (DOS) which it needed for the Apple II microcomputer. As the article describes, Apple was forced to buy in a Disk Operating System (DOS) from an outside company to work with the Apple II and the innovative disk drive Steve Wozniak had designed as they didn't have anyone in house who could develop the DOS in time.

Apple DOS was critical in the success of the Apple II and hence Apple itself which may not have survived long enough to develop the Lisa and Macintosh if the Apple II had not been the success it was. Indeed the Apple II continued to be a success well into the late 1980s.

Apple DOS was written by Paul Laughton, and it together with Woz's disk drive and VisiCalc (the first killer app) made the Apple II a success in business. Interestingly it was developed on a minicomputer, stored on punch cards and debugged on that system before being put on Apple's microcomputer (more about this can be read here on Laughton's own website). This is nothing new of course, the Apple II itself was used to write early Lisa and Macintosh system software.