[alsa-devel] ALSA 1.1.8 Release - POLLRDNORM undefined

[Takashi Iwai]

On Wed, 09 Jan 2019 17:22:36 +0100,
Jay Foster wrote:
> 
> 
> 
> On 1/9/2019 3:10 AM, Takashi Iwai wrote:
> > On Tue, 08 Jan 2019 18:00:18 +0100,
> > Jay Foster wrote:
> >> I am attempting to build the 1.1.8 release of alsa-utils and getting
> >> an error about POLLRDNORM (and others) undefined.  This error comes
> >> from axfer/waiter-select.c.  axfer/waiter-select.c includes
> >> "waiter.h", which includes "poll.h".  This build is for a linux
> >> target.
> >>
> >> poll.h includes sys/poll.h which includes bits/poll.h, which only
> >> defines POLLRDNORM (and others) when __USE_XOPEN is defined (which it
> >> is not).
> >>
> >> However, linux/poll.h includes asm/poll.h which includes
> >> asm-generic/poll.h which does define POLLRDNORM (and others).
> >>
> >> Should I change my build to define__USE_XOPEN or should I patch
> >> waiter.h to include linux/poll.h instead of just poll.h?
> > Which libc are you using?  The POSIX man page (man poll.h) mentions
> > POLLRDNORM defined there, at least, on my system with glibc 2.27.
> >
> >
> > thanks,
> >
> > Takashi
> >
> >
> This is a legacy ARM product using glibc 2.9.  Neither of the
> approaches I mentioned above actually worked.  <linux/poll.h> is the
> kernel headers, which results in a duplicate definition of struct
> pollfds.  The other approach (I added 'CFLAGS=-D_XOPEN_SOURCE=500' to
> the make command line, and other variations) failed elsewhere due to
> missing or mismatched function prototypes (ref <features.h>).
> 
> I got this to work by patching axfer/waiter.h to add the missing
> defintions, based on those found in <asm-generic/poll.h>.

I wonder what is supposed on such a system.  poll() needs these POLL*
constant definitions, and they aren't available by simple poll.h?
That's weird.  What does "man poll.h" say in your version?


thanks,

Takashi