[erlang-questions] Can't update xterm title bar from Erlang

Roger Lipscombe roger@REDACTED
Mon May 15 13:17:41 CEST 2017


I don't need the line feed from the shell:

    echo -ne '\e]0;Hello\a' ; sleep 5

...works fine.

But, in terms of line-feed-flushes-buffers, maybe.

Except that I immediately output something else with a line feed, and the
terminal (gnome-terminal, Linux Mint) shows *something* for the escape
sequence. It looks almost-correct, but it's hard to tell.

I suspect something to do with how Erlang has configured the tty for
(maybe) raw mode, but I don't understand enough about how that works.

On 15 May 2017 at 11:17, Alex S. <alex0player@REDACTED> wrote:

> What I’ve noticed is you don’t output the line feed, which might mean that
> the IO buffer isn’t getting flushed by default. Although I am not sure.
>
> 12 мая 2017 г., в 22:28, Roger Lipscombe <roger@REDACTED>
> написал(а):
>
> I have the following:
>
>     put_progress(Format, Args) ->
>         io:put_chars(user,
>                      [tsl(), io_lib:format(Format, Args), fsl()]),
>         io:put_chars(user,
>                      [colored(), io_lib:format(Format, Args), reset(),
> "\n"]),
>         ok.
>
>     tsl() -> "\e]0;".
>     fsl() -> "\a".
>     colored() -> "\e[1;44m".
>     reset() -> "\e[0m".
>
> That is: output the same message to the title bar (tsl, fsl are the tput
> capability names; see https://serverfault.com/a/23998/7027), and then
> (for now) also output it in colour, so that I can see if it's being called
> correctly.
>
> Unfortunately, something is messing with my tsl() and fsl() escape codes.
> The coloured text is coming out correctly, but the other stuff's garbage.
> The escape codes are correct; I've tested them at the bash prompt with
> "echo -e '\e]0;Hello\a'".
>
> So... what's screwing with them when they're output from ct_run?
>
> Interestingly, if I try the same at the Erlang prompt, it hangs the shell
> until I press Ctrl+C twice, at which point the text is output, but still
> messed up.
>
> Cheers,
> Roger.
> _______________________________________________
> erlang-questions mailing list
> erlang-questions@REDACTED
> http://erlang.org/mailman/listinfo/erlang-questions
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-questions/attachments/20170515/800396b1/attachment.htm>


More information about the erlang-questions mailing list