title: about fork and execve system call
body: <p>It is said that <code>fork</code> system call creates a clone of the calling process, and then (usually) the child process issues <code>execve</code> system call to change its image and running a new process. Why this two-step?</p>
  
  <p>BTW, what does <code>execve</code> stand for?</p>