core-bundle/src/Resources/contao/library/Contao/File.php
public static function putContent($strFile, $strContent)
	{
		$objFile = new static($strFile);
		$objFile->write($strContent);
		$objFile->close();
	}
public static function putContent($strFile, $strContent)
	{
		$objFile = new static($strFile);
		$objFile->write($strContent);
		$objFile->close();
	}
Write to a file

@param string $strFile    Relative file name
@param string $strContent Content to be written