in reply to SIGTTIN when running with &
Any time you run an external program, you run this risk. If the program you are running tries to open the tty to which it is connected, this will happen. I have seen this a great many times with batch perl processes.
I guess you have a few options. With rsh, i believe someone mentioned the -n option, which fixes this. With some other programs (and even some XS modules) where a similar option is not avaialble, i have found i normally have to open a second terminal, start the program with a nohup, and close that terminal... or run programs using cron or at.
from the frivolous to the serious