Bug#793672: DPkg::Post-Invoke hook output gets slightly messed up when using progress bar

[Antonio Ospite <ao2@ao2.it>]

On Thu, 3 Mar 2016 17:48:23 -0300
Tomasz Nitecki <tnnn@tnnn.pl> wrote:

> retitle 793672 DPkg::Post-Invoke hook output gets slightly messed up when using progress bar
> reassign 793672 apt
> thanks
> 
> 
> Hey,
>

Hi Tomasz,

> I believe that this issue is not limited to how-can-i-help, but it will actually
> mess up any output coming from DPkg::Post-Invoke hook.
>

I suspected it was a more general issue, thanks for confirming it.

> Sample script that outputs a few line of text during post-invoke:
> 
> /etc/apt/apt.conf.d/99outputest:
> DPkg{Post-Invoke {"echo '1st line\n2nd line\n3rd line\n4th line'";};};
> 
> When run with progress bar, progress bar output will corrupt the script output.
> 
> What's interesting, is that when run for the first time, it will work fine. Only
> second and subsequent calls will corrupt output (this also applies to how-can-i-help
> output corruption from the original report).
> 
> BTW, Nowadays, you can simply run 'apt ...' instead of setting 'pkg::Progress-Fancy'.
> 

JFYI, the progress bar is enabled by default only for apt, it still
has to enabled explicitly using Dpkg::Progress-Fancy to also work in
apt-get and aptitude (after the fix for #816520 gets packaged).

Ciao ciao,
   Antonio

-- 
Antonio Ospite
http://ao2.it

A: Because it messes up the order in which people normally read text.
   See http://en.wikipedia.org/wiki/Posting_style
Q: Why is top-posting such a bad thing?