úÎ%ä%     Safe-Infered A timeout of  tells  select(2) to never time out, while   s us sets the timeout parameters to s seconds and us  microseconds.  Safe-Infered# readFds writeFds exceptFds timeout calls the   select(2)' function with the file descriptors in readFds as the 7 FD set to watch for read readiness, and similarly for writeFds  and  exceptFds, with timeout$ specifying the timeout. The return  value is that of the call.  Safe-Infered action returns a   immediately. The result of  action will be placed in said   . If the   is full  when action6 completes, the return value is lost (the action does  not wait for an empty  ). This version of  takes an additional  , and returns  its content or4 the result of the IO action, depending on which is * available first. Note that the action is not interrupted if the   5 is the winner, so you may want to make sure it doesn't  stick around forever. !The function was made to support  , the reason this @ library exists, and may not be useful outside of that context.  Safe-InferedThis version of # immediately returns and makes the  return value of the  select(2) call available as a     . See  for argument information. #The parameters are the same as for , except for the  addition of a  -. The function returns as soon as either the   select(2) has completed, or the   is full. /The return value is either the return value of  select(2) , or the  content of the   . If the   becomes available first,  then the  select(2)0 call may hang around forever or until it times  out (as specified by the  parameter). If the  select(2)  returns before the   is available, the   is guaranteed  to be left in place. (Incidentally,   is the task I really wanted to C accomplish, and solving it just turned into this little library).      Safe-Infered   action returns an  immediately. The result of  action will be placed in said  . If the  is full when  action: completes, the return value is lost (the action does not  wait for an empty ).      Safe-Infered This version of # immediately returns and makes the  return value of the  select(2) call available as an    . See  for argument information.             select-0.1System.Posix.IO.Select.TypesSystem.Posix.IO.SelectControl.Concurrent.STM.TMVarIOSystem.Posix.IO.Select.STMControl.Concurrent.MVarIOSystem.Posix.IO.Select.MVarselectOrTakeTMVarTimeoutTimeNever MicrosecondsSecondsselectrunrunOrTakeTMVarstm-2.3Control.Concurrent.STM.TMVarTMVarbaseForeign.C.TypesCIntGHC.MVarMVar