23 Nov
2005
23 Nov
'05
7:32 p.m.
Warning : My knowledge of OS-9 is beased entirely on the 6809 (8 bit)
version, I've never used a 68K version. I suspect some of the things that
I think were 'misisng' on the 6809 version (like shell variables and
wildcards) are present in the stnadard shell of the 68K version. But
anyway...
To begin to understand it, consider it to be a CP/M
clone with
multi-user extensions. List the files in the system directory and most
Internally it's not a bit like CP/M
of them will be vaguely familiar utilities. I believe
"DIR" was the
command. If not, use commands from other common OS's as it was the same
as one of them (LIST maybe?).
A few things....
At least in the 6809 version there was no equivalent to the PATH for
lookin for commands. At any time, a user had 2 default directories. One
was the data directory, the other the execution directory. The latter is
what was searched for commands.
File paths were somewhat unix-like. But you don't mount all the disks
into one filesystem. Rather, the first part of each complete file path is
the device name. I remeember floppies called /D0, /D1. etc and hard
drives /H0, /H1, etc. Some machines have a device /DD which is a copy of
the device descriptor for the drive you want to be the default.
So, for example, a file on the second floppy drive might be specified
soemthing like : /D1/pascal/demo.pas
Two of the built-in commands of the stnadard shell were CHD (to set the
data directory) and CHX (to set the execution directory). Typically the
latter is set to /D)/CMDS (that being the normal equivalent of /bin on a
unix box). Note that if you chanve floppies, you have to type CHX /D0/CMDS
(even if the directory was /D)/CMDS both before and after the change),
since IIRC, it stores a pointer to some part of that directory in RAM,
not the name iteslf.
IIRC, the stnadard name for the directory command was DIR, but of course
as it was simply a program loaded and run from the execution directory,
it could be called anything.
-tony