State Substate Target True False Action BadFcn
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A 0 isdrive 1 1 savedrive skip
1 isroot 2 2 appendpath skip
2 ispath 2 3 appendpath skip
B 3 isfname 4 ERR savefname errmsg
C 4 isext 5 5 saveext skip
D 5 isEOR OUT ERR cleanup errmsg