title: What value does $(shell pwd) give?
body: <p>Going through a MakeFile I find</p>
  
  <p><code>PROJECT_ROOT = $(shell pwd)</code></p>
  
  <p>What value does it give?</p>
  
  <p><code>$SHELL</code> gives the shell and <code>$PWD</code> gives present working directory
  But what does $(shell pwd) give?</p>