If you actually do want to exit the program, and pass some exit code to the calling process, there's nothing wrong with using exit.  In the above snippet, you could place the exit after the print, for example.

...
print "exit code: $exitcode, message: '$msg'\n";
exit $exitcode;
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But note that negative exit codes are typically interpreted unsigned, e.g. in a Unix shell, -1 would turn into 255  (-2 into 254, etc.):

$ perl -e "exit -1"
$ echo $?
255
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