2016-10-02 01:58:03 +05:30
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a() {
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(exit 2)
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echo a:$?
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(kill -s USR1 $$; echo b:$?; exit 3)
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echo c:$? # does not execute
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(exit 4)
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}
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trap "echo Trap; return" USR1
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a
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echo d:$?
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# It's debatable what is the correct value above.
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2016-10-26 16:45:35 +05:30
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# Does 'return' in trap see $? == 2 or $? == 3?
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2016-10-02 01:58:03 +05:30
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# IOW: after (kill..), does shell first wait for its completion
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# and sets $?, then checks pending signals and runs a trap handler,
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2016-10-26 16:45:35 +05:30
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# or does it first check pending signals and runs handler?
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2016-10-02 01:58:03 +05:30
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# hush does the former, and prints 3.
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