We often need to do "something" to about half the machines, then
do "something else" to the other half. So add a hack to toggle the
"tagged" status of the machines.
This is implemented by means of the F1 menu; the command characters
"o" and "O" can toggle the "tagged" status of the machines.
PR: 211682
Submitted by: maintainer
that library calls do not do that. Therefore, it's SIGCHLD handling causes
a hang in wait() as openpty() already does that. Fix this by using waitpid()
with WNOHANG.
Diagnosed by: jhb
Tested by: dhw (earlier version)