From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v4 0/3] vfs: Define new syscall umask2 [formerly getumask]
Date: Wed, 13 Apr 2016 12:37:42 -0700
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On 04/13/16 12:05, Richard W.M. Jones wrote:
> v3 -> v4:
>
>   - Rename the syscall: getumask becomes umask2.
>
>   - Add flags parameter, with one flag (UMASK_GET_MASK).
>
>   - Expand the rationale for this change in the first commit message.
>
>
> It's not possible to read the process umask without also modifying it,
> which is what umask(2) does.  A library cannot read umask safely,
> especially if the main program might be multithreaded.
>

I wouldn't say "if"; that is the case when it matters.

I have to say I'm skeptic to the need for umask2() as opposed to 
getumask().  I would also like to be able to get the umask of another 
process, which would argue for adding it to /proc anyway.

	-hpa