From: Philip Oakley Date: Fri, 28 Dec 2018 20:31:56 GMT Subject: Re: [PATCH 0/2] Improve documentation on UTF-16 Message-ID: In-Reply-To: <34d4f912-2ec3-9dd1-f5fb-aad6a26e1464@kdbg.org> On 28/12/2018 08:59, Johannes Sixt wrote: > Am 28.12.18 um 00:45 schrieb brian m. carlson: >> On Thu, Dec 27, 2018 at 08:55:27PM +0100, Johannes Sixt wrote: >>> But why do you add another U+FEFF on the way to UTF-8? There is one >>> in the >>> incoming UTF-16 data, and only *that* one must be converted. If >>> there is no >>> U+FEFF in the UTF-16 data, the should not be one in UTF-8, either. >>> Puzzled... >> >> So for UTF-16, there must be a BOM. For UTF-16LE and UTF-16BE, there >> must not be a BOM. So if we do this: >> >>    $ printf '\xfe\xff\x00\x0a' | iconv -f UTF-16BE -t UTF-16 | xxd -g1 >>    00000000: ff fe ff fe 0a 00 ...... > > What sort of braindamage is this? Fix iconv. > > But as I said, I'm not an expert. I just vented my worries that > widespread existing practice would be ignored under the excuse "you > are the outlier". > > -- Hannes For ref, I dug out a Microsoft document [1] on its view of BOMs which can be compared to the ref [0] Brian gave [1] https://docs.microsoft.com/en-us/windows/desktop/intl/using-byte-order-marks [0] https://unicode.org/faq/utf_bom.html#bom9 Maybe the documentation patch ([PATCH 1/2] Documentation: document UTF-16-related behavior) should include the line ", because we encode into UTF-8 internally,", and a link to ref [0], and maybe [1] Whether the various Windows programs actually follow the Microsoft convention is another matter altogether . -- Philip