$file_handle = fopen('fixy.txt', 'r');

while ($line = fgets($file_handle)) {
    $output[] = array(
        'title' => trim(substr($line, 0, 50)),
        'code' => trim(substr($line, 50, 5)),
        'date' => trim(substr($line, 55, 8)),
        'writer' => trim(substr($line, 63, 50))
    );
}

fclose($file_handle);

$information['type1'] = array(
    array('name' => 'title', 'position' => 0, 'length' => 50),
    array('name' => 'code', 'position' => 50, 'length' => 5),
    array('name' => 'date', 'position' => 55, 'length' => 8),
    array('name' => 'writer', 'position' => 63, 'length' => 50)
);
//there will also be a type 2, 3 and so on...

$type = $information['type1'];

...
while ($line = fgets($file_handle)) {
    ...
    $type['name'] => trim(substr($line, $type['position'], $type['length'])),...
    ...
}

$information['type1'] = array(
    array('name' => 'title', 'position' => 0, 'length' => 50),
    array('name' => 'code', 'position' => 50, 'length' => 5),
    array('name' => 'date', 'position' => 55, 'length' => 8),
    array('name' => 'writer', 'position' => 63, 'length' => 50)
);

$type = $information['type1'];

$file_handle = fopen('fixy.txt', 'r');

while ($line = fgets($file_handle))
{
    $output[$type['name']] = trim(substr($line, $type['position'], $type['length']));
}

fclose($file_handle);