[Buildroot] [PATCH] Raspberry Pi - WiringPi Library Package

Guillermo Amaral g at maral.me
Fri Jul 12 04:30:56 UTC 2013


Howdy Baruch,

On Fri, Jul 12, 2013 at 06:24:30AM +0300, Baruch Siach wrote:
> Hi Guillermo,
> 
> On Thu, Jul 11, 2013 at 11:22:58AM -0700, Guillermo Amaral wrote:
> > On Thu, Jul 11, 2013 at 09:06:03PM +0300, Baruch Siach wrote:
> > > On Thu, Jul 11, 2013 at 10:55:30AM -0700, Guillermo Amaral wrote:
> > > > The Raspberry Pi doesn't go down to 2.6.y, the oldest supported version is
> > > > 3.2.27. :)
> > > 
> > > If this is the case, then there is no reason to make O_CLOEXEC a no-op.
> > > 
> > > > So there should be no need to do the kernel check, since the package is RPi
> > > > specific.
> > > > 
> > > > The problem here was that O_CLOEXEC was not defined with the default uclibc
> > > > and older versions of glibc.
> > > 
> > > The O_CLOEXEC define comes with the kernel headers used to build the 
> > > toolchain, not from the C library.
> > 
> > I didn't say it didn't. I'll clarify, if __USE_GNU and/or __USE_XOPEN2K8 don't
> > get defined at some point O_CLOEXEC is not getting defined. My guess is that
> > they get defined by *libc, feel free to correct me if I'm wrong.
> 
> The code below builds just fine on my machine:
> 
> #include <sys/types.h>
> #include <sys/stat.h>
> #include <fcntl.h>
> 
> void func(void) { open("f", O_RDWR | O_CLOEXEC); }

Congratulations, I'm very proud. Have a beer on me! (B)

G

P.S.

$ host/usr/bin/arm-linux-gcc -c x.c
x.c: In function ‘func’:
x.c:5:38: error: ‘O_CLOEXEC’ undeclared (first use in this function)
x.c:5:38: note: each undeclared identifier is reported only once for each
function it appears in

$ cat x.c
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

void func(void) { open("f", O_RDWR | O_CLOEXEC); }

-- 
gamaral http://about.me/gamaral


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