
  check_invar - Performs model checking of invariants
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   check_invar [-h] [-m | -o output-file] [invar-expression]
   
   Performs invariant checking on the given model. An invariant is a set
   of states. Checking the invariant is the process of determining that
   all states reachable from the initial states lie in the invariant.
   Invariants to be verified should be provided as simple formulas
   (without temporal operators) in the input file via the INVARSPEC
   keyword or directly at command line.
   
   All the fairness conditions associated with the model are ignored.
   
   If an invariant does not hold, a proof of failure is demonstrated.
   This consists of a path starting from an initial state to a state
   lying outside the invariant. This path has the property that it is the
   shortest path leading to a state outside the invariant.
   
   Command options:
   
   -m
          Pipes the output generated by the program in processing
          INVARSPECs to the program specified by the PAGER shell variable
          if defined, else through the UNIX "more" command.
          
   -o output-file
          Writes the output generated by the command in processing
          INVARSPECs to the file output-file.
          
   invar-expression
          An invariant to be verified.
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   Last updated on 990119 20h08
