title: Get "E484: Can't open file /tmp/foo/a" when using system("wget") in Vim
body: <p>I have a small function that throws an error. This is the function:</p>
  
  <pre><code>function! GetPHPInfo(function_name)
    let page = system("wget -q -O - 'php.net/" . a:function_name)
    " let page = system("wget -q -O - 'google.com'")
    return page
  endfunction
  </code></pre>
  
  <p>When I use wget from php.info, I get this error:</p>
  
  <pre><code>E484: Can't open file /tmp/vRXHL5q/7
  </code></pre>
  
  <p>But not when I use wget from google.com. I assume it's because google is a smaller page than php.net, and therefore can be written. How do I change the allowed size for tmp files?</p>