linux-kernel - Re: [PATCH tracing/kprobes v2 1/5] tracing/kprobes: Rename special variables syntax

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 7 Oct 2009 00:42:53 +0200
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	Steven Rostedt <rostedt@...dmis.org>
Cc:	Masami Hiramatsu <mhiramat@...hat.com>,
	Ingo Molnar <mingo@...e.hu>,
	lkml <linux-kernel@...r.kernel.org>,
	systemtap <systemtap@...rces.redhat.com>,
	DLE <dle-develop@...ts.sourceforge.net>,
	Thomas Gleixner <tglx@...utronix.de>,
	Arnaldo Carvalho de Melo <acme@...hat.com>,
	Mike Galbraith <efault@....de>,
	Paul Mackerras <paulus@...ba.org>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Christoph Hellwig <hch@...radead.org>,
	Ananth N Mavinakayanahalli <ananth@...ibm.com>,
	Jim Keniston <jkenisto@...ibm.com>,
	"Frank Ch. Eigler" <fche@...hat.com>
Subject: Re: [PATCH tracing/kprobes v2 1/5] tracing/kprobes: Rename special
	variables syntax

On Mon, Oct 05, 2009 at 08:12:53PM -0400, Steven Rostedt wrote:
> On Mon, 2009-10-05 at 21:26 +0200, Frederic Weisbecker wrote:
> > On Mon, Oct 05, 2009 at 12:59:01PM -0400, Masami Hiramatsu wrote:
> > > As far as I can see in arch/*/include/asm/ptrace.h, all registers start with
> > > alphabets :-). So, I'd like to suggest renaming sp-vars to '_sp-vars'.
> > >
> > > Then, we will have;
> > > - $local-vars
> > 
> > 
> > There is a risk of bash collision.
> 
> I actually prefer the "$" notation. As for bash collision, it is common
> for shell script writers to be able to distinguish a variable from bash.
> Yes we can backslash it, or quote it. But when I see a $var it sticks
> out to me that it is a variable. It's not hard to get around. For
> example, type:
> 
> $ echo "hello $DISPLAY"' or $DISPLAY'
> 
> and see what you get.
> 
> Makefiles and Perl use '$' for variables those that need to handle it
> with bash can easily cope with it.
> 
> So my vote is to keep the '$'. It is the most intuitive to what it
> means.


Hrrmm...

I fear about future complains, but I may be somehow biased in
that my usual usecases of bash don't involve '$' characters to
protect, so it's not something I'm used to.

Whatever choice we make, there are either downsides in the prefix
self meaning, the collisions or the shell intrpretation.

Now you are two who prefer that, let's pick this one :)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/