core-bundle/src/Resources/contao/library/Contao/File.php
protected function createIfNotExists()
	{
		// The file exists
		if (file_exists($this->strRootDir . '/' . $this->strFile))
		{
			return;
		}

		// Handle open_basedir restrictions
		if (($strFolder = \dirname($this->strFile)) == '.')
		{
			$strFolder = '';
		}

		// Create the folder
		if (!is_dir($this->strRootDir . '/' . $strFolder))
		{
			new Folder($strFolder);
		}

		// Open the file
		if (!$this->resFile = $this->Files->fopen($this->strFile, 'wb'))
		{
			throw new \Exception(sprintf('Cannot create file "%s"', $this->strFile));
		}
	}
protected function createIfNotExists()
	{
		// The file exists
		if (file_exists($this->strRootDir . '/' . $this->strFile))
		{
			return;
		}

		// Handle open_basedir restrictions
		if (($strFolder = \dirname($this->strFile)) == '.')
		{
			$strFolder = '';
		}

		// Create the folder
		if (!is_dir($this->strRootDir . '/' . $strFolder))
		{
			new Folder($strFolder);
		}

		// Open the file
		if (!$this->resFile = $this->Files->fopen($this->strFile, 'wb'))
		{
			throw new \Exception(sprintf('Cannot create file "%s"', $this->strFile));
		}
	}
Create the file if it does not yet exist

@throws \Exception If the file cannot be written