Re: ogg123 hanging, parked, and _lwp_park

[Andrew Doran <ad%netbsd.org@localhost>]

On Sat, Jun 28, 2008 at 09:41:26PM -0500, Jeremy C. Reed wrote:

> xfmedia using libxine kept hanging on me.
> 
> I installed ogg123 (vorbis-tools) and it hung also when it first printed 
> output but never began playing. top said "parked".
> 
> ktrace showed it was hanging here:
> 
>   2985      2 ogg123   RET   write 12592/0x3130
>   2985      2 ogg123   CALL  _lwp_unpark(1,0x7f7ffa713028)
>   2985      2 ogg123   RET   _lwp_unpark 0
>   2985      2 ogg123   CALL  write(2,0x51da00,0x98)
>   2985      2 ogg123   GIO   fd 2 wrote 152 bytes
>        "\r                                                                    
> \
>                \rTime: 00:00.77 [02:22.02] of 02:22.79  ( 25.7 kbps)  
> Output B\
>         uffer  66.7% \r"
>   2985      2 ogg123   RET   write 152/0x98
>   2985      1 ogg123   RET   _lwp_park 0
>   2985      1 ogg123   CALL  _lwp_park(0,0,0x7f7ffa713028,0x7f7ffa713028)
>   2985      2 ogg123   CALL  write(4,0x7f7ffa729340,0x4000)

It looks like an application bug. You can generate a core file from it and
then try to get a backtrace of the thread that is sleeping, and debug it
that way.

(gdb) info threads
(gdb) thread X
(gdb) bt

or

(gdb) thread apply all bt

Andrew