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Re: remote protocol run length encoding
- To: jtc@redback.com
- Subject: Re: remote protocol run length encoding
- From: Andrew Cagney <ac131313@cygnus.com>
- Date: Fri, 03 Sep 1999 17:40:34 +1000
- CC: gdb@sourceware.cygnus.com
- Organization: Cygnus Solutions
- References: <5m1zcgh90m.fsf@jtc.redbacknetworks.com>
"J.T. Conklin" wrote:
> The problem is in the way the run length is encoded. 29 is added to
> the run length, which yields a printable ASCII character for extents
> between 3 and 97 characters. Unfortunately, this includes '$', '#',
> '+', and '-' which can exacerbate problems caused by transport layer
> glitches. It's been my experience that such glitches occur all too
> often to ignore, so the protocol itself must be made as robust as
> possible.
I'll document this restriction.
> The run length encoding used by Cisco's remote protocol varient is
> safe, as it uses two hex digits to represent the length. Perhaps we
> could add a variable which selected which RLE method to use? At the
> same time, we could add support for encoding of command packets. It
> could be quite useful for register and memory writes.
This is sounding like the existing rle method should be deprecated.
Can you think of any reliable way of probing for RLE?
Andrew