Because the curdir isn't the same. Maybe /home/jerry doesn't exist. Or
maybe your home dir isn't /home/jerry (you can set a home
directory to anything you like, it doesn't HAVE to be /home/USRPRF...
that's just the default) or because the curdir isn't the same as the
home directory because something else changed the curdir... lots of
possibilities, but for some reason, the tstcat.sh file isn't in your
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