From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#22050: [PATCH v4 1/2] linux-boot: Add make-static-device-nodes.
Date: Fri, 15 Dec 2017 23:37:19 +0100
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To: Danny Milosavljevic <dannym@scratchpost.org>
Cc: 22050@debbugs.gnu.org

Danny Milosavljevic <dannym@scratchpost.org> skribis:

> Hi Ludo,
>
> On Fri, 15 Dec 2017 10:41:37 +0100
> ludo@gnu.org (Ludovic Court=C3=A8s) wrote:
>
>> This looks good, but would it be enough to do:
>>=20
>>   (mkdir-p (dirname (string-append "/dev/" name)))
>
> mkdir permission needs to be specified to be #o755.
>
> I've seen some variants in guix - but they are all buried somewhere deep:
>
> ./gnu/services/cups.scm:        (define (mkdir-p/perms directory owner pe=
rms)
> ./gnu/services/dns.scm:      (define (mkdir-p/perms directory owner perms)
> ./gnu/services/mail.scm:      (define (mkdir-p/perms directory owner perm=
s)
> ./guix/build/utils.scm:(define (mkdir-p dir)
> ./guix/build/graft.scm:(define* (mkdir-p* dir #:optional (mode #o755))

Oh, I didn=E2=80=99t think we had this many variants.

> I don't feel good relying on magical unspecified permissions in code requ=
ired to boot the system.  I think mkdir-p itself subtracts the umask or som=
ething.  Is the umask guaranteed to be 0 at the point of usage of make-stat=
ic-device-nodes ?

I=E2=80=99m not 100% sure.  You could set =E2=80=98umask=E2=80=99 explicitl=
y given that it=E2=80=99s
single-threaded and all at this point, but it=E2=80=99s probably clearer to
explicitly specify the mode like you did initially.

So I guess you can forget my comment and apply the original variant (or
perhaps explicitly copy =E2=80=98mkdir-p/perms=E2=80=99 so we can find it m=
ore easily
when we factorize!).

Thanks for explaining!

Ludo=E2=80=99.