Revert to using just the currentTask ivar, using the lock for any access. NSTask is documented as thread-unsafe, so it shouldn't be accessed multi-threaded without a lock.  
Revert to using just the currentTask ivar, using the lock for any access. NSTask is documented as thread-unsafe, so it shouldn't be accessed multi-threaded without a lock.  
ycaihua/skim-app,ycaihua/skim-app,WoLpH/skim,WoLpH/skim,WoLpH/skim,WoLpH/skim,ycaihua/skim-app,ycaihua/skim-app,WoLpH/skim,ycaihua/skim-app