title: Golang converting string to int64
body: <p>I want to convert a string to an int64. What I find from the <code>strconv</code> package is the <code>Atoi</code> function. It seems to cast a string to an int and return it:</p>
  
  <pre><code>// Atoi is shorthand for ParseInt(s, 10, 0).
  func Atoi(s string) (i int, err error) {
          i64, err := ParseInt(s, 10, 0)
      return int(i64), err
  }
  </code></pre>
  
  <p>The ParseInt actually returns an int64:</p>
  
  <pre><code>func ParseInt(s string, base int, bitSize int) (i int64, err error){
       //...
  }
  </code></pre>
  
  <p>So if I want to get an int64 from a string, should I avoid using Atoi, instead use ParseInt? Or is there an Atio64 hidden somewhere?</p>