How does TERM=dumb support work?

[Carsten Mattner]

On Tue, Sep 25, 2012 at 6:30 PM, Carsten Mattner
<carstenmattner at gmail.com> wrote:
> On Tue, Sep 25, 2012 at 6:17 PM, Augie Fackler <raf at durin42.com> wrote:
>> On Tue, Sep 25, 2012 at 11:08 AM, Carsten Mattner
>> <carstenmattner at gmail.com> wrote:
>>> On Tue, Sep 25, 2012 at 3:07 PM, Augie Fackler <raf at durin42.com> wrote:
>>>>
>>>> On Sep 25, 2012, at 6:42 AM, Carsten Mattner <carstenmattner at gmail.com> wrote:
>>>>
>>>>
>>>> What you're seeing actually strikes me as a bug: this makes anything
>>>> with a progress bar unusable in emacs shell-mode, for example. Is
>>>
>>> Made another test and the hg progress bar seems not affected
>>> by TERM=dumb at all and works the same way with TERM=9term.
>>> The trick to make hg log behave is either to use a dumb PAGER
>>> or omit some of the fancy /usr/bin/less options and most certainly
>>> also disable the color extension.
>>
>> I'm not sure where log is coming from in this discussion. I thought we
>> were talking about progress?
>
> Sorry, it's the next test I did after cloning.
>
> Either I'm confused or did test something else but while retesting
> this again hg clone's progress bar didn't fit in 9term regardless of TERM=dumb.
> Maybe some code was believing the terminal was wider than it is.
>
> I must confess that I must have probably tested with the modified hgrc
> before but now I had to use TERM=dumb so that progress did not emit
> \r as I suppose that's the issue with 9term. IIRC 9term doesn not support \r.
> That makes more sense in the context of the s390 patches.
>
>>> Either way hg behaves better because you can configure ~/.hgrc
>>> to not emit escape sequences in hg log while I failed to configure
>>> the same for git.
>>
>> I'm not sure why you're seeing this. Is this pure plan9, or plan9 from
>> user space on some other environment?
>
> plan9port but I can also test in 9vx if I can get hg working there.
> It's probably best if you do some independent testing.
>
>>> The question is what's different in hg's progress extension that makes
>>> hg clone not emit 9term-incomprehensible output.
>>
>> Progress just uses \r judiciously to overprint a line. It should still
>> be disabled when TERM=dumb, and I've given myself a bug in bugzilla to
>> track that.
>
> Seems to be disabled. Without TERM=dumb it prints many many lines.
>
> Another minor issue is that after "adding manifests" there's a blank
> line and wrong indenting (# means space and #=# blank line):
> [...]
> adding manifest
> #=#
> #adding file changes
> #=#
> #added 3398 changesets[...]
> #=#
> #7494 files updates

Why didn't I use \n and \s to denote the characters? Sorry.