read_fairness - read a fairness constraint
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   read_fairness [-h] <file>

   Read a fairness constraint, and associate this constraint with the FSM
   of  the  flattened network. An existing constraint associated with the
   FSM is lost. Subsequent verification procedures are performed relative
   to  the  new  constraint. Note that, by default, the flattened network
   has  the  constraint  TRUE,  indicating  that  all paths are fair. The
   command  build_partition_mdds  (or init_verify) must have already been
   invoked on the flattened network, before this command is called.

   Currently,  only  Buchi  constraints  are  supported. A Buchi fairness
   constraint  is given by a list of individual Buchi conditions, B1, B2,
   ...,  Bk,  where  Bi  is a set of FSM states. A state is fair if there
   exists  an  infinite  path  from  that  state  that intersects each Bi
   infinitely often.

   The  conditions  are  specified  by a file containing at least one CTL
   formula  (see the [1]VIS CTL and LTL syntax manual). In particular, Bi
   is  defined  by a CTL formula, which represents the set of states that
   makes  the  formula  true (in the absence of any fairness constraint).
   References  to  signal  names  in the network should be made using the
   full hierarchical names. Note that the support of any wire referred to
   in  a  formula  should  consist  only  of latches. Each CTL formula is
   terminated by a semicolon.

   Example:  In the three conditions below, B1 contains those states that
   have  a  next  state  where  cntr.out  is RED, B2 contains those where
   timer.active  is  1, and B3 contains those states for which every path
   from the state has tlc.request=1 until tlc.acknowledge=1.

  EX(cntr.out=RED);
  (timer.active=1);
  A(tlc.request=1 U tlc.acknowledge=1);


   Command options:

   -h
          Print the command usage.

   <file>
          File containing the set of Buchi conditions.
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   Last updated on 20050519 10h16

References

   1. file://localhost/projects/development/hsv/vis/common/doc/ctl/ctl/ctl.html