title: makefile shell and pipe
body: <p>I need help: the following command line is not working </p>
  
  <pre><code>TESTS := $(shell cat test_cases_file | egrep -v ^\s*(#|$) ) 
  all: $(TESTS) 
  </code></pre>
  
  <p>when I launch:</p>
  
  <pre><code>make all
  </code></pre>
  
  <p>I get an error something like "call of shell command is not finished."</p>