[PHP] 파일 읽고 쓰기 fOpen fWrite

* fOpen

$filename='test.txt';
$dataFile = fopen( $filename, "r" );
 if ( $dataFile )
 {
  while (!feof($dataFile))
  {
  $buffer = fgets($dataFile, 4096);
  }
 }
fclose($dataFile);

* fWrite

filename='test.txt';
$dataFile = fopen( $filename, "w" );
 if ( $dataFile )
 {
   fwrite($dataFile ,"1234567890\n");
 }
fclose($dataFile);