This regex seems to match both your examples.

   /(?:\s|^)(.{1,27})(?=\s|$)/g
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You must do some padding, with sprintf or pack for example, to append extra padding spaces.

@padded = map { sprintf "-%27s", $_ } /(?:\s|^)(.{1,27})(?=\s|$)/g;

@padded = map { pack "A27", $_ } /(?:\s|^)(.{1,27})(?=\s|$)/g;
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