On 07/20/2013 08:24 PM, Steve Willoughby wrote:

On 20-Jul-2013, at 16:37, Jim Mooney <cybervigila...@gmail.com> wrote:
If only Bill Gates hadn't chosen '\', which is awkward to type and
hard to make compatible - but I think he figured his wonderful DOS
would be a Unix-killer, reign supreme, and there would be no
compatibility problem. All I can say to that is, "thank God for
competition."  ;')

If I recall correctly, the earliest versions of DOS (which supported directories) allowed you to configure your environment to use / as a 
directory separator so you could really use A:/path/to/directory for things.  That wasn't the default since, if I were to guess, they had 
already adopted the use of "/" to introduce command-line switches which was the existing syntax on systems like CP/M and various 
DEC operating systems of the same era, so it would be ambiguous as to whether "foo/bar" referred to a file "bar" in the 
directory "foo" or the file "foo" with a "/bar" switch applied to its usage.


A few more details, from my memory. DOS 1.x had various kludges to emulate CP/M, including the use of / for a switch character. When DOS 2 was introduced, the first to explicitly support a hard disk, and the new fat16, subdirectories were added. The default syntax for that was the backslash. When Wang's MSDOS was introduced (2.01), a pair of calls were added to set and test switchar, which was supposed to be used for command interpreting. The idea was to use '-' as the switch character, leaving / to be used to separate directories. Unfortunately, most commands in COMMAND.COM ignored the new function, and very few third party programs paid any attention at all.

The OS paid no attention to the switch, and just treated the slash and backslash as interchangeable.

Wang's switch character defaulted to "-", but they had little influence on the DOS application world.

Having already burned that bridge, flipping the slash the other way to \ for directory 
separators probably seemed like a good compromise at the time.  In hindsight, I think it 
would have been better to just make a clean break at some early point and just change to 
"/" for directories, but that's never quite as easy to see as the right move at 
the time.

I'm just glad they didn't start out using the VMS-style directory syntax or our 
paths would look like $DISK:[foo.bar.baz]file.ext;2

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DaveA

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