- From: Francois Yergeau <FYergeau@alis.com>
- Date: Thu, 03 Oct 2002 13:31:53 -0400
- To: ietf-charsets@iana.org
McDonald, Ira wrote: > This IETF standard should NOT encourage the use of leading BOM in > streams of UTF-8 text. The current text neither encourages nor discourages BOM usage, it only points out the existence of the convention and gives some caveats (like the uncertainty when stripping a BOM and the possible breakage of digital sigs and the like). > The optional use of leading BOM in UTF-8 (as > I know Martin said) destroys the crucial property that US-ASCII > is a perfect subset of UTF-8 and that US-ASCII can pass _without > harm_ through UTF-8 handling software libraries. This totally clashes with my understanding. Can you please explain how the existence of the BOM convention in UTF-8 changes anything to the interpretation of US-ASCII strings that by definition never contain a BOM? > UTF-8 never needs a 'byte-order' signature. This is unfortunately not true, except in the limited realm of properly internationalized protocols with proper implementations and no reliance on humans to correctly label things. Which leaves out quite a few things, prominent among them file systems: my disks are full of text files in either Latin-1, UTF-8 or UTF-16, and the BOM is the only thing that distinguishes them. Many of those files result from a "Save as" where the original was properly labelled in some protocol, but the metadata simply gets lost. -- François
Received on Thursday, 3 October 2002 13:32:45 UTC