Read a CSV, process it and output a CSV

remap-csv.php

<?php

if (count($argv) != 3) {
  die('Usage: php remap-csv.php <infile> <outfile>');
}


// in / out files are $argv[1] and $argv[2]
$in  = fopen($argv[1], "r");
$out = fopen($argv[2], "w");

$line_num = 1;
while (($data = fgetcsv($in, 1000, ",")) !== FALSE) {
  // test data. In this example test for 4 columns
  if (count($data) != 4) {
    echo "Bad line number [$line_num]\n";
    print_r($data);
  }
  else {
    // remap some fields 1 and 3
    fputcsv($out, array($data[1], $data[3]), ',', '"');
  }
  $line_num++;
}

// close files
fclose($in);
fclose($out);