Here's two ways of doing it: 
while () {
    $_ = substr($records, $p, index($records, "\n", $p) - $p);
    last if (!$_); $p += length($_) + 1;
    # do whatever with data now in $_
}

while ($records =~ /(.*?)\n/g) {
    # do whatever with data now in $1
}

[download]
I benchmarked both for 10,000 iterations on a 1,000 record string. The substr took 22 seconds vs 46 seconds for the regex. Both assume there's a \n on the end of the string.

Using split directly cuts it to 10 seconds, but requires about twice the memory: 

for (split(/\n/, $records)) {
    # do whatever with data now in $_
}

[download]

In reply to Re: using a variable as a filehandle by TedPride
in thread using a variable as a filehandle by bear0053

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