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Date: Tue, 28 Nov 2017 11:54:58 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [PATCH] vfs: Add PERM_* symbolic helpers for common file
 mode/permissions
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Mon, Nov 27, 2017 at 2:06 AM, Ingo Molnar <mingo@kernel.org> wrote:
> >
> >
> > +/*
> > + * Human readable symbolic definitions for common
> > + * file permissions:
> > + */
> > +#define PERM_r________ 0400
> > +#define PERM_r__r_____ 0440
> > +#define PERM_r__r__r__ 0444
> 
> I'm not a fan. Particularly as you have a very random set of
> permissions (rx and wx? Not very common), but also because it's just
> not that legible.
> 
> I've argued several times that we shouldn't use the defines at all.
> The octal format isn't any less legible than any #define I've ever
> seen, and is generally _more_ legible.
> 
> What's wrong with just using 0400 for "read by user"?

Yeah, the octal format isn't all that bad - at least relative to the symbolic 
obfuscation defines.

Thanks,

	Ingo