On Tue, 2016-11-08 at 20:53 +0100, Marc Lehmann wrote: > On Tue, Nov 08, 2016 at 04:02:53PM +0000, Ian Campbell <[email protected]> > wrote: > > > > This was reported to docker https://github.com/docker/docker/issues/281 > > 11 when doing a docker pull there is a multi-line scrolling progress > > bar, when running under rxvt-unicode the final line is duplicated. > > Ok, after analyzing it, docker relies on undocumented behaviour in xterm. > Basically, docker does "move cursor 0 lines up" and expects the terminal > to move up one line, which xterm does, but urxvt doesn't. To try it out, > run this near the bottom line of the screen: > > printf "\n\n\e[0B\e[0A---" > > (Try with a plain shell prompt when unsure) > > This will leave the --- (and the prompt) in the last line of the screen > with urxvt, and in the second to last line with xterm.
That's indeed what i see. Thanks for the explaination, I was pretty confused by it all! > In summary: docker outputs a lot of "move cursor 0 characters" commands, > which are undocumented, non-ANSI, and behave different in different > terminals. That likely "explains" the comment at https://github.com/docker/docker/blob/master/pkg/jsonmessage/jsonmessage.go#L195 i.e. the author was using some terminal with a particular behaviour and was lead astray. Anywy, I agree with all you say and will investigate using termcap since that seems like the best option (assuming I can find a decent termcap library for go...) Thanks for your help & input! Ian. _______________________________________________ rxvt-unicode mailing list [email protected] http://lists.schmorp.de/mailman/listinfo/rxvt-unicode
