[mosh-users] Alternate character set support (line grpahics) with terminfo

[Vincent Lefevre]

On 2014-03-20 13:42:09 +0100, Florian Bruhin wrote:
> * Vincent Lefevre <vincent-mosh at vinc17.net> [2014-03-20 13:29:33 +0100]:
> > Hi,
> > 
> > It seems that mosh doesn't support the alternate character set
> > for terminfo-based utilities:
> > 
> > In an xterm terminal:
> > 
> > $ tput smacs; echo "mq>"
> > └─>
> > 
> > but if I run "mosh localhost":
> > 
> > $ tput smacs; echo "mq>"
> > mq>
> > 
> > I'm under Debian/unstable, with mosh 1.2.4a-1+b1 Debian package.
> 
> That's a feature ;)

No, xterm supports the alternate character set, so that since mosh
declares to emulate xterm by setting TERM=xterm, it must support
ACS (possibly in an optional way, for people who don't like ACS
and don't intend to use it).

> See http://mosh.mit.edu/#techinfo :
> 
>     Only Mosh will never get stuck in hieroglyphs when a nasty program
>     writes to the terminal. (See Markus Kuhn's discussion of the
>     relationship between ISO 2022 and UTF-8[0].)
> 
>     [0] http://www.cl.cam.ac.uk/~mgk25/unicode.html#term

I *never* get stuck in hieroglyphs with any terminal. So, this is
pointless.

> Why would you need this anyways, when you can have Unicode?

For programs that were written a long time ago, and which still work
with any terminal[*]... except mosh.

[*] even those that don't support the alternate character set, as
long as they use a terminal name that doesn't claim to support it
(in such a case, ASCII characters are just used).

-- 
Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)