Subject: Re: pppd changes
To: None <current-users@NetBSD.ORG>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: current-users
Date: 05/26/1998 13:34:16
>> it would be nice if you could describe shortly what this "asyncmap"
>> does.  According to the man it escapes control sequences that can't
>> be transferred over the line.  But that starts for 0x00 with a value
>> of 0x00000001 and so on.

Right, I think.

> It's a bitmask for the first 32 characters.  A value of 0x00000001
> means "escape ASCII 0x01", a value of 0x00000002 means "escape ASCII
> 0x02", a value of 0x00000003 means "escape ASCII 0x01 and 0x02", etc
> etc.

I'm pretty sure this is off-by-one: 0x00000001 means "escape 0x00",
0x00000002 means "escape 0x01", etc, up to 0x80000000 meaning "escape
0x1f" - with, as you imply, various values ORed together, so that (for
example) 0xedb88320 means to escape characters 0x1f, 0x1e, 0x1d, 0x1b,
0x1a, 0x18, 0x17, 0x15, 0x14, 0x13, 0x0f, 0x09, 0x08, and 0x05.  (And
the first person to correctly identify where I got that 0xedb88320
value from wins one gen-u-wyne real live piece of email from me!  You
need only make sure you include a working email address for you.  But
hurry, there's only one grand prize! :-)

If 0x00000001 corresponded to 0x01, then (a) there would be no way to
indicate that 0x00 should be escaped and (b) the 0x80000000 bit would
correspond to the ordinary space character, which essentially never
needs to be escaped.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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