Re: [PATCH v7 00/16] tracing: Hist trigger snapshot and onchange additions

Masami Hiramatsu
2018-11-29T14:54:15Z

On Thu, 29 Nov 2018 22:52:25 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> > For that system, I'm using Gnome terminal 3.24.2 and GNU bash, version
> > 4.4.12(1)-release (x86_64-pc-linux-gnu) (Ubuntu 17.10).
> >
> > If I change 'echo' to '/bin/echo' in e.g. prlog() it works fine, so it
> > must be the inbuilt bash echo that's not doing the right thing. I
> > thought it might be the xpg_echo option, but 'shopt -s xpg_echo'
> > doesn't have any effect.
> >
> > I also tried on a Fedora 28 system (GNOME terminal 3.28.2, GNU bash,
> > version 4.4.23(1)-release (x86_64-redhat-linux-gnu), and it worked
> > fine.
> >
> > Also, tried a Ubuntu 18.04.1 system (GNOME Terminal 3.28.1, GNU bash,
> > version 4.4.19(1)-release (x86_64-pc-linux-gnu) and in that case the
> > colors worked fine, but still got the '-e -n' and newlines in the
> > output:
> >
> > -e -n [28] (instance) event trigger - test histogram modifiers
> > -e [PASS]
> > -e -n [29] (instance) event trigger - test histogram trigger
> > -e [PASS]
> >
> > Again, substituting '/bin/echo' in prlog() fixed things in this case
> > too. I guess the builtin bash 'echo' can't be relied on..
>
> OK, then we should use /bin/echo for avoiding this issue.

Ah, I found that usually ubuntu system use "dash" instead of
"bash" for the alias of "sh", and its builtin echo command doesn't
accept "-e". So if the first option is "-e", it treats all arguments
are output string, including -e.

Anyway, still using /bin/echo is the best solution.

Thank you,

--
Masami Hiramatsu <mhiramat@kernel.org>