If you need to run with retries why not look at AnyEvent::Timer::Retry or Action::Retry

If you are forking off a child, that uses qx(), then why not read the basic $? (provided your scripts actually do exit non-zero on errors)

fbrm@monastery:~/$ mkdir /tmp/x
fbrm@monastery:~/Downloads$ perl -e 'print qx(ls /tmp/x); print $?'
0
fbrm@monastery:~/$ perl -e 'print qx(ls /tmp/y); print $?'
ls: cannot access /tmp/y: No such file or directory
512
fbrm@monastery:~/$
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