Mail Archives: opendos/1997/05/02/02:14:30
Um... "details" is probably the wrong word, but just to spell out some
possibly ways of implementing things, so we can see what could happen...
A. Suppose there is a new command available in command.com and
autoexec.bat called "mount" (just to be consistent with the Unix
command name) that does the job of assign, join and subst, as well as
net use/map at the moment - i.e. it allows a drive or directory (could
be remote, could require going through a special driver) to mounted
anywhere else (as a drive letter or as a directory).
B. Suppose that, unlike horrible old *nix, you don't usually specify a
"-t fstype" parameter, nor have to have an /etc/fstab file to say what
to mount automatically at startup (I guess you could still do either,
if you wantted to). Instead, it would ask all loaded drivers if they
can handle it. In some cases that might be involved (e.g. if you
specify a "UNC" name then something is goingto have to see what
protocol that remote computer expects).
C. This all requires a smallish IFS manager, that matches up requests
for a resource to handlers. It probably also manipulates internal DOS
structures that would normally be attacked by ASSIGN, etc. Just
possibly this IFS could be a device driver itself, that replaces a
chunk of old DOS when installed. Or it could be a TSR that is called by
the MOUNT command the first time a mount is attempted that cannot be
handled by old-fashioned hacking of wierd internal DOS tables. But
ideally it would be there from startup, to detect and use non-FAT
partitions, add Long FileName support, etc.
D. So a filesystem is normally installed in two steps: one is installing
a driver (not needed if simply FAT), the next step is when a particular
partition/directory/whatever is mounted that uses this type.
E. Now, suppose you can also install attributes. Either at the same
time as installing a filesystem (technically, probably at the time of
an actual mount that supports it), or seperately (some module could be
added that says "whenever something wants to know (this) attribute
within the file region I control (default is / perhaps) then I can
supply it".
F. There are special cases are registerring an attribute provider; I
suppose the protocol would be a some sort of list in memory at the time
of the call, and often the job of the IFS is to simply match up
requests for attributes (coming from some new system call) to these
lists, but there would be special provision for Access Control Lists
and permissions in general (two-way traffic in info is needed, for user
name etc), and file "type" (e.g. created on a CR-LF system, needs a WP
document processor in this class...").
Oops! gotta go home... bye!
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Mark Aitchison, Physics & Astronomy \_ Phone : +64 3 3642-947 a.h. 3371-225
University of Canterbury, </ Fax : +64 3 3642-469 or 3642-999
Christchurch, New Zealand. /) E-mail: phys169 AT csc DOT canterbury DOT ac DOT nz
#include <disclaimer.std> (/' "per haps ad gloria"
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