in reply to Odd workings of split
It seems odd that, if what you want to do is to "remove newlines," that you do not use the obvious regex to do that. If you want to "take the command up to the first newline if any," split will work fine, in a short subroutine, with an if-statement to supply an empty-string for undef. Two (gasp!) lines of code ... problem solved.
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