Help please: process stuck on pty

[Warren Burstein]

In playing around with child processes connected to a parent thru
ptys, sometimes the children survive the parent.  When this happens,
and I try to open the pty next time thru, the open("/dev/pty??", 2)
call hangs.  I didn't see anything about this in pty(4) but from
reading the source to script(1) it seems to me that if a pty is in
use open will fail, not hang.  What am I doing wrong here?  Also,
is there some way to ensure that children don't survive the parent?

thanks