Script3.pl would be run if script2.pl died.

To prevent it, use

script1.pl
script2.pl && script3.pl
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Script2 will always be run regardless of how script1 exits. Script3 will only be be run if script2 succeeds -- Ie. returns 0, which it won't if it dies or exits with any value other than 0.

You can also do

script1 || script2;
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In which case, script2 will only be run if script1 fails.

P:\test>perl -e"exit 1" && echo succeeded || echo failed
failed

P:\test>perl -e"exit 0" && echo succeeded || echo failed
succeeded

P:\test>perl -e"die" && echo succeeded || echo failed
Died at -e line 1.
failed
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You can also group commands

(prog1 && prog1) || (prog3 || prog4)
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