I've already sent this to the alsa-user list, but may be this a better place to ask:
I have a problem using 32 bit (i386) playback applications on a 64 bit (x86_64) CentOS4/RHEL4 based kernel (based on kernel 2.6.9).
I've installed alsa-driver, alsa-lib and alsa-utils 1.0.13 (newer versions of alsa-driver don't build with this kernel)
If I try to run a 32 bit copy of aplay on a 64 bit machine that doesn't support hardware mixing (e.g. HDA NVidia) - i.e. uses dmix by default, I get:
aplay: pcm_write:1268: write error: Invalid argument
and /var/log/messages reports:
Sep 4 16:45:37 wstemp-b kernel: ioctl32(aplay:28133): Unknown cmd fd(3) cmd(40045402){00} arg(ffffae88) on /dev/snd/timer Sep 4 16:45:37 wstemp-b kernel: ioctl32(aplay:28133): Unknown cmd fd(5) cmd(c008551a){00} arg(080678a0) on /dev/snd/controlC0 Sep 4 16:45:37 wstemp-b kernel: ioctl32(aplay:28133): Unknown cmd fd(5) cmd(c008551b){00} arg(080678a0) on /dev/snd/controlC0 Sep 4 16:45:37 wstemp-b kernel: ioctl32(aplay:28133): Unknown cmd fd(3) cmd(000054a0){00} arg(00000320) on /dev/snd/timer
I've done some searching to find a solution - and found out that in more recent kernels, snd-ioctl32 has been obsoleted - and if I do use a more modern kernel, then using a 32 bit version of aplay works OK on a newer 64 bit kernel.
However, for other (not sound related) reasons, I need to run the RHEL4/CentOS4 2.6.9 kernel ...
I had a look at the alsa-driver code, and acore/ioctl32/timer32_new.c contains:
#if 0 /* ** FIXME ** * The following four entries are disabled because they conflict * with the TCOC* definitions. * Unfortunately, the current ioctl32 wrapper uses a single * hash table for all devices. Once when the wrapper is fixed * with the table based on devices, they'll be back again. */ MAP_COMPAT(SNDRV_TIMER_IOCTL_START), MAP_COMPAT(SNDRV_TIMER_IOCTL_STOP), MAP_COMPAT(SNDRV_TIMER_IOCTL_CONTINUE), MAP_COMPAT(SNDRV_TIMER_IOCTL_PAUSE), #endif
If I change the '#if 0' to '#if 1', recompile and reload with this new snd-ioctl32 module, then the 32 bit aplay works without an error ... although /var/log/messages still reports:
Sep 4 17:05:26 wstemp-b kernel: ioctl32(aplay:28926): Unknown cmd fd(3) cmd(40045402){00} arg(ffffadb8) on /dev/snd/timer Sep 4 17:05:26 wstemp-b kernel: ioctl32(aplay:28926): Unknown cmd fd(5) cmd(c008551a){00} arg(080678a0) on /dev/snd/controlC0 Sep 4 17:05:26 wstemp-b kernel: ioctl32(aplay:28926): Unknown cmd fd(5) cmd(c008551b){00} arg(080678a0) on /dev/snd/controlC0
... but at least I get sound out!
So, what is the danger of using these 'disabled' ioctls?
I can't find any reference to 'TCOC* definitions' - what are these ???
Thanks
James Pearson