title: Minimal implementation of sprintf or printf
body: <p>I'm working on an embedded DSP where speed is crucial, and memory is very short.</p>
  
  <p>At the moment, sprintf uses the most resources of any function in my code. I only use it to format some simple text: <code>%d, %e, %f, %s</code>, nothing with precision or exotic manipulations.</p>
  
  <p>How can I implement a basic sprintf or printf function that would be more suitable for my usage?</p>