> Just curious, does that mean that in "normal terminals" (not docker) it uses `FRAME_TERMINAL_CODING (f)
> ` but in docker it uses `safe_terminal_coding`?
Looks like that, yes. It would mean that the docker doesn't define a
locale environment which defines a usable codeset. I know nothing
about dockers, so I have no idea how could this happen.
Okay, for information here is the env and locale inside docker containers:
```
address@hidden:~$ docker run -it --rm silex/emacs:master env
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=b1366c3c8820
TERM=xterm
EMACS_BRANCH=master
EMACS_VERSION=master
HOME=/root
address@hidden:~$ docker run -it --rm silex/emacs:master locale
LANG=
LANGUAGE=
LC_CTYPE="POSIX"
LC_NUMERIC="POSIX"
LC_TIME="POSIX"
LC_COLLATE="POSIX"
LC_MONETARY="POSIX"
LC_MESSAGES="POSIX"
LC_PAPER="POSIX"
LC_NAME="POSIX"
LC_ADDRESS="POSIX"
LC_TELEPHONE="POSIX"
LC_MEASUREMENT="POSIX"
LC_IDENTIFICATION="POSIX"
LC_ALL=
```
Out of curiosity I might investigate why this happens, but maybe there lies some unharmful bug in emacs there that went unnoticed for long because `safe_terminal_coding` just works.
Is all the detection happening in `setup_coding_system`? I maybe modify Emacs' source so it reports what is being detected and it might give us clues about what differs in the docker container.
I suspect the same problem happens in LXC containers.
Regards,
Philippe