* doc/coreutils.texi (dd invocation): Document the behavior of 'dd' on multibyte characters and some unspecified behavior that will be documented in a future POSIX release [1].
[1] https://austingroupbugs.net/view.php?id=1959 --- doc/coreutils.texi | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/doc/coreutils.texi b/doc/coreutils.texi index d37cf2471..8ae81e110 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -9280,6 +9280,17 @@ @node dd invocation The @samp{lcase} and @samp{ucase} conversions are mutually exclusive. +@c https://austingroupbugs.net/view.php?id=1959 +POSIX leaves the behavior of @samp{lcase} and @samp{ucase} unspecified +on multibyte characters. GNU @command{dd} only converts one byte at a +time, because multibyte characters may cross block boundaries and case +conversion may change the length of characters. + +POSIX also leaves the behavior of @samp{lcase} and @samp{ucase} +unspecified if used with @samp{ascii}, @samp{ebcdic}, or @samp{ibm}. +GNU @command{dd} will perform the case conversion and then perform the +character set conversion. + @item sparse @opindex sparse Try to seek rather than write NUL output blocks. -- 2.52.0
