This assumes there are no newlines in the original string (at least not in an inconvenient place): 
use Text::Wrap qw(wrap $columns);

$columns = 30;
my $trimmed = wrap('', '', $str);
$trimmed =~ s/\n.*/.../s;

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In reply to Re: In search of a better way to trim string by runrig
in thread In search of a better way to trim string by kiat

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