title: How to create a PDF/A file in Swift?
body: <p>I'd like to create a PDF/A file in my iOS app but don't really know where to start. </p>
  
  <p>My actual code (which generates a simple PDF) is:</p>
  
  <pre><code>_ = UIGraphicsBeginPDFContextToFile(temporaryPdfFilePath, paperSize, nil)
  UIGraphicsBeginPDFPageWithInfo(paperSize, nil)
  let currentContext: CGContextRef = UIGraphicsGetCurrentContext()!
  </code></pre>
  
  <p>...drawing...</p>
  
  <pre><code>UIGraphicsEndPDFContext()
  </code></pre>
  
  <p>Is there any API or something else to follow?</p>