Unidentified subject!

[optima]

my linux fan : thank you very mach!
I has try this method before I mail my first  letter.
I found if my code don't invoke "waitfor()". I can get the 
inputstream of the new process. so I try use printstream to 
write new password to the stream and invoke the "waitfor()"
but the process do not go on .(I use the "ps " see it).