f91ad6b0b7
SIGTTIN or SIGTTOU, we just disable use of the prompt for the controlling terminal (and put a ^Z next to it in a ``show who'' listing). Unfortunately, we need to enable a timer to ``poll'' for the terminal having us as the controlling pgrp when a user does a ``bg''. If anyone knows how to do this better - please speak up (is there any indication to the process group leader when it's ctrling terminal gets tcsetpgrp()'d back ?)....