title: Pattern to get string between two specific words/characters using grep
body: <p>I need to extract email address from a string like this (I'm making a log parser):
  <code>&lt;some text&gt; from=someuser@somedomain.com, &lt;some text&gt;</code></p>
  
  <p>with <code>egrep</code> (or <code>grep -Eo</code>). So the string needs to be pulled out only between <code>"from="</code> and <code>","</code> , because the other parts of log contain email addresses too, like <code>to=</code> and <code>etc
  </code></p>