title: How can I disable commandline Curl's TCP_NODELAY option?
body: <p>I'm diagnosing a weird networking problem, which (I think) I've narrowed down to misbehaving HTTP clients or servers and some HTTP1.1 pipelining and / or Nagle's algorithm interaction. I'm trying to disable TCP_NODELAY in curl as a test.</p>
  
  <p>Curl's man page says:</p>
  
  <pre><code>--tcp-nodelay
        Turn on the TCP_NODELAY option. See the curl_easy_setopt(3) man page for details about this option.
  
        Since 7.50.2, curl sets this option by default and you need to explicitly switch it off if you don't want it on.
  
        Added in 7.11.2.
  </code></pre>
  
  <p>It then never explains how to explicitly switch it off. I tried setting <code>export CURLOPT_TCP_NODELAY=0</code> in the environment, but curl still mentions in its output:</p>
  
  <pre><code>* TCP_NODELAY set
  </code></pre>
  
  <p>Searching the internet or Stackoverflow is also not giving me an answer. </p>
  
  <p>So how can I turn it off?</p>