difficult SIGCHLD / pipe hang

[Joe Buehler]

>    10  588509 [sig] ksh 620 wait_sig: awake
>   345  588854 [sig] ksh 620 wait_sig: processing signal 20
>   184  589038 [sig] ksh 620 wait_sig: Got signal 20
>   163  589201 [sig] ksh 620 sig_handle: signal 20
>   157  589358 [sig] ksh 620 sig_handle: signal 20, about to call 0x6DE24420
>  -305  589053 [proc] ksh 620 sig_send: returning 0 from sending signal 20
>   636  589689 [proc] ksh 620 wait_subproc: looping
> # last message from 620
>     3  589692 [sig] ksh 620 setup_handler: suspending mainthread

Looking at the code, it looks as though setup_handler() never finishes,
because there are strace messages printed before it exits (but the end of
strace output is as you see above).  I'll have to add some strace output
and try and see what is going on.
-- 
Joe Buehler