Duplicating ASCII bel in the tty driver (was Re: Changing tty drivers)

[Carl Edman]

In article <1884 at necisa.ho.necisa.oz> boyd at necisa.ho.necisa.oz (Boyd Roberts) writes:
   In article <CEDMAN.90Oct17195500 at lynx.ps.uci.edu> cedman at lynx.ps.uci.edu (Carl Edman) writes:
   >
   >Summary: I think it is a good and simple idea, which (in contrast
   >to almost all other suggestions made in this group) actually
   >would work.
   >

   No, no, no, no!  It may be simple, but it's just not _right_.
   When you write ASCII bel to some file/tty/whatever you expect
   to get _one_ ASCII bel.  Not two.  Just one.

   It's just a YANDS (Yet Another Nickel and Dime Solution).  A proposal
   to break the tty driver for no good reason, except that it's cheap.

   Consider a communications protocol that runs across RS-232 via the
   tty driver.  This protocol uses full 7 bit ASCII (or 8 bits if you like).
   Every once in a while it is _possible_ that an ASCII bel may appear
   in the byte stream of this protocol (maybe a real bel, maybe ASCII 7
   makes up part of a CRC checksum).  And at this point another bel is
   inserted, corrupting the protocol which will result in circuit shutdown. 

No, no , no, no ! You didn't read what I wrote I explicitly stated that
this would only apply to fixed hardwired "dumb" terminals in public
access areas. There it is that the problem of spoofs is the greatest
and where this feature would be most effective. On this kind of terminal
NO compilcated file transfer protocoll is going to run and the system
managers will know the kind of terminals they have well enough to
always install the right bell character.

On the other hand, for dialup lines on which most file transfer protocolls
are run there is little (altough not no) chance of spoofs. So this
would NOT apply to them.

It's O.K. , but I would be grateful if people READ the post they replied
to first, BEFORE replying. The argument in the preceeding 2 paragraphs
is exactly the one made in my original post and (I think you will agree
after having read it) largly invalidates your complaint.

	Carl Edman



Theorectial Physicist,N.:A physicist whose   | Send mail
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