title: How to write int to file using write system call and read them exactly as written?
body: <p>How can I write int, float or other types to a file using the write system call of UNIX?
  I want to do so without using any lib function like <code>fprintf</code> or <code>fwrite</code>.</p>
  
  <p>I want to use file descriptor and not the <code>FILE*</code>.</p>
  
  <p>After opening again, the file must be read exactly as written, without needing to know what size to read.</p>