[alsa-devel] ALSA 1.1.8 Release - POLLRDNORM undefined

[Takashi Iwai]

On Wed, 09 Jan 2019 21:33:11 +0100,
Takashi Iwai wrote:
> 
> 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?

... or maybe it's only about a few of them that are missing?


Takashi