This is your line 6: 
2009-12-24_,5587

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After your 1st split, $content[0] contains the string 2009-12-24_, as desired. Then you split that string on the underscore character. The resulting array, @datesplit, now has only one element. The problem arises because you expected that array to contain (at least) two elements in your next line: 
$csvprint = "$datesplit[0],$datesplit[1],$content[1]\n";

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If this line represents valid input data, then you must check how many elements are in your @datesplit array if you want to avoid this warning. Perhaps you want to do something like this: 
if (@datesplit > 1) {
    $csvprint = "$datesplit[0],$datesplit[1],$content[1]\n";
}
else {
    $csvprint = "$datesplit[0],$content[1]\n";
}

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In reply to Re: reading files in a directory with range operator. by toolic
in thread reading files in a directory with range operator. by avanta

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