Hi,
after https://lists.gnu.org/archive/html/coreutils/2021-02/msg00003.html
(unreleased), the behavior of cat -E was changed so that it prints "^M$"
for "\r\n" line endings.
Whenever it sees a \r "cat -E" checks if the byte after is a \n, however
that \n might be the sentinel value that is inserted at the end of a buffer.
This is a problem in two cases:
- When a \r is at the end of the input. `printf "\r" | cat -E` will
print "^M", even though there is no "\n" after the "\r". FWIW,
tests/misc/cat-E.sh expects a "^M" for a trailing "\r", but I think
that's wrong.
- When the file is too big to fit into one buffer. If you try to "cat
-E" a big file (mutliple megabytes) that consists of only "\r", cat will
print a few "^M" whenever it hits the end of a buffer in the middle of
the file and at the end.
Michael
