my previous fix too (using wdp_heads controller value) and check
0 heads case too.
Other fixes from Bruce:
2) Fix dk_timeout from 2 to about 4 seconds.
3) wdcontrol not retried on internal error.
4) wdwait return check changed ( "!=0" to "<0" into wdsetctlr,
"<0" to "!=0" into wdgetctlr).