vtool: Usage Message
      A tool to execute a command using one or more features managed by the
      Altair Engineering-LM license manager. The VOV_JOBCOUNTER environment
      variable must point to the license manager vovserver instance using the
      format of port@host,instance (eg: 5557@lmhost,licmon).
      Multiple instances can be specified by separating them with a colon
      (eg: 5557@lmhost1,licmon1:6667@lmhost2,licmon2). If multiple instances
      are specified, each subsequent instance will be queried if the requested
      tokens were not granted by the previous instance in the list.
      By default, each instance must be able to grant the requested number of
      tokens in whole.  However, scavenging mode (-s) can be used to allow
      each instance to partially fulfill the request.
      % vtool [-v] [-refresh <S>] -f <feature1> <tokens1> \
           [-f <feature2> <tokens2> ...] <command ...>
      -v                -- Increase verbosity.
      -f <feature> <N>  -- Check-out N tokens of specified feature.
                           If N is negative, queueing will be enabled for the
                           absolute value of N tokens.
                           It is an error for N to be zero.
      -refresh     <S>  -- Specify refresh cycle (time-spec) for tokens
                           (default is 600 seconds), meaning that
                           the tokens are refreshed every 10 minutes.
                           Setting a refresh cycle of 0 disables
                           the refresh.
      -s                -- Scavenging mode. When VOV_JOBCOUNTER is set to a
                           colon delimited list of license servers, a check
                           out from each server will occur until the target
                           number of tokens has been reached. If queuing is
                           enabled, only the last server will enter queuing
                           mode regardless of its license capability.
       TSTP             -- Release licenses and suspend execution.
       CONT             -- Resume execution.
       HUP              -- Caught and ignored
       TERM             -- Caught and ignored
       QUIT             -- Caught and ignored
      vlmstat vovcounters
      % vtool -f lic_drc -1 -f lic_hdrc -1 sleep 10
      % vtool -s -f lic_drc 3 sleep 10
      % vtool -f lic_drc 3  -refresh 2m  sleep 10000