I think you have an error in your specification. The last bit of code you give specifies a single array reference as the first value of an array. You probably want one line per array value?

Anyway, you can use backticks for this

my @captured = `./myexecutable.out -O option1 -W option2 -T option3`;
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or, if you want the output in an array reference

my $captured = [(`./myexecutable.out -O option1 -W option2 -T option3`
+)];
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