🚀 go-pugleaf

I wrote...
> .....  One affects the way you can check for a directory existing
> by testing if the file dirname\.. exists, 
                         ^^^^^^^^^^
I think I made a mistake there, I think it was dirname\nul, and it was only
DRDOS 5 that differed from MSDOS, but that's from memory.

Another difference was that DRDOS 5 treated the wildcard string "*ABC.*" as an
error, but MSDOS and DRDOS 6 both treat it as "*.*" (so beware when doing
something like DEL *X.*  ... it doesn't just delete filenames ending in "X"
before the dot, but deletes all the files!).. That was a bug/limitation in
MSDOS from the beginning which some people/programs have come to expect.

I've heard that there are lots of differences (between versions of MSDOS, as
well as between DRDOS & MSDOS) in handling wildcards in the COPY command, e.g.
what do you expect the following to do??

  COPY *.BAT+*.LOG *.NEW


Another difference is that under most versions of MSDOS, the first device
driver in CONFIG.SYS can look at a register and find (and modify!) the
tokenised copy of the rest of the config.sys lines.  This is very undocumented
but used by at least two config.sys chooser programs, which won't work under
DRDOS (of course, you'd want to use DRDOS's own way of choosing options in
config.sys anyway, and it might not work with later MSDOS anyway).

Another difference is that a ";" after filenames can mean the start of a
password under DRDOS, but are often ignored by MSDOS.  Not very important,
except some network software that allows copying of files from a VAX can take
over the version numbers from VMS and they become passwords under DRDOS.

Beyond that, the differences are mainly improvements, which could possibly be
viewed as incompatibilities (e.g. if you had a program called "gosub" that was
referred to in a batch file, or any other filename that is now an internal
command, but that's at least patchable).

I'd be interested to hear of differences lists from others.

Mark Aitchison, University of Canterbury.