title: Formatting Unix timestamp with ctime in c
body: <p>I'm trying to format a 10-digit Unix time stamp (currently a  string) using ctime.</p>
  
  <p>However, ctime() expects a parameter of type time_t, not a string.</p>
  
  <p>What must I do before I can use ctime?
  In other words, can I easily convert the string into a time_t? </p>