From: "Ned Freed" <ned.freed@xxxxxxxxxxx> To: "TomPetch" <sisyphus@xxxxxxxxxxxxxx> Cc: "ietf" <ietf@xxxxxxxx> Sent: Friday, December 23, 2005 7:13 PM Subject: Re: Troubles with UTF-8 <snip> > > (Unicode > > lacks a no-op, a meaningless octet, one that could be added or removed without > > causing any change to the meaning of the text). > > NBSP is used for this purpose. > Thank you for that; it is not something I have seen documented before. > > Other protocols use a terminating sequence. NUL is widely used in *ix; some > > protocols specify that NUL must terminate the text, some specify that it must > > not, one at least specifies that embedded NUL means that text after a NUL must > > not be displayed (interesting for security). Since UTF-8 encompasses so much, > > there is no natural terminating sequence. > > This simply isn't true. NUL is present in Unicode and is commonly used as a > terminator. > Not sure which bit isn't true. I agree NUL is present in Unicode and agree that some protocols use it as a terminator and prohibit its use in the text. But some allow it in the text in which case another form of termination is needed or else the NUL must be escaped/encoded. Presented with a comparable problem where XML is in use, one WG has chosen to use an illegal XML sequence as a terminator so what I was fishing for is if there were any parallels with UTF-8, which has many illegal sequences of octets and so it would be easy to choose one as a terminator. Tom Petch > Ned. _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf