+ # From man ps:
+ # D uninterruptible sleep (usually IO)
+ # R running or runnable (on run queue)
+ # S interruptible sleep (waiting for an event to complete)
+ # T stopped by job control signal
+ # t stopped by debugger during the tracing
+ # W paging (not valid since the 2.6.xx kernel)
+ # X dead (should never be seen)
+ # Z defunct ("zombie") process, terminated but not reaped by its parent
+ #
+ # Additionally, not documented in ps man page:
+ # I Idle
+ #