title: Setting a default value for %sysget return value
body: <p>I have the following code:</p>
  
  <pre><code>%let my_var = %sysget(MY_VAR);
  %put &amp;=my_var;
  </code></pre>
  
  <p>If I run the following code, <code>my_var</code> will be defined and print:</p>
  
  <pre class="lang-sh prettyprint-override"><code>#!/bin/bash
  
  export MY_VAR=1;
  /sas/scripts/sas my_script.sas
  </code></pre>
  
  <p>But without that <code>export</code> statement, <code>my_var</code> is effectively not defined, and the script fully executes, without error.</p>
  
  <pre class="lang-sh prettyprint-override"><code>#!/bin/bash
  
  /sas/scripts/sas my_script.sas
  </code></pre>
  
  <p>I want to set a default value for what's returned from <code>%sysget</code> in case the variable isn't defined. How can I do that?</p>