ah, indeed! much easier that way. i had totally forgotten that you could get
that from ps!  
though, yeah, you'll need something tricky to call wakeup, at minimum a 
debugger. in practicality, one would probbaly just reboot the box. 
not just disk waits, though. other stuff can do this too, though it is 
generally on waits from io hardware. 4.3BSD poorly handled TK50 failures 
(which were all too common) and i'd cross my fingers every time i read a
tape, as it might wedge and the tape drive was useless until reboot (as 
well as the process being unkillable) because another process already had 
the drive- not even to reset the drive! 

isildur

On Fri, 8 Nov 2002, Andrew Brown wrote:
> not so.
> 
> % ps -T -opid,wchan,nwchan,stat,command
>   PID WCHAN    WCHAN STAT COMMAND
>   310 pause cf798084 Ss   -csh (tcsh)
>   528 -            0 R+   ps -T -opid 
> 29968 -            0 T    ssh -A cafebabe 
> 
> the numeric wait channel is what you want.  to wake up the sleeping
> process, though, *will* require the use of the debugger.  or an lkm.
> you can't simply call wakeup() from userland.