I believe you want ^ with the m modifier. 
while ("abc\ndef\nghi" =~ /^(.)/mg) {
   print("$1\n");  # a,d,g
}

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In reply to Re: Regex question - either starts, or has newline prefixing? by ikegami
in thread Regex question - either starts, or has newline prefixing? by ultranerds

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