title: Command not found, make: Error 127,
body: <p>I have this make file which compiles successfully:</p>
  
  <pre><code>CCC = g++
  CFLAGS = -c -g -Wall
  CCFLAGS = $(CFLAGS)
  LDFLAGS = -g
  
  common_objects = main.o tokens.o
  flex_objects = flex_scanner.o 
  hand_objects = hand_scanner.o 
  
  both: flex_scanner hand_scanner
  
  flex_scanner: $(flex_objects) $(common_objects)
      $(CCC) $(LDFLAGS) $(flex_objects) $(common_objects) -o flex_scanner
  
  flex_scanner.o: flex_scanner.l
      flex -it flex_scanner.l &gt; flex_scanner.cc
      $(CCC) $(CCFLAGS) flex_scanner.cc
  
  clean:
      /bin/rm -f hand_scanner flex_scanner $(hand_objects) $(flex_objects) \
          $(common_objects) flex_scanner.cc
  
  test: both
      flex_scanner &lt; test1 &gt; flex_test1.output
      hand_scanner &lt; test1 &gt; hand_test1.output
  </code></pre>
  
  <p>But when I try to run <code>make test</code> I get the following error:</p>
  
  <pre><code>flex_scanner &lt; test1 &gt; flex_test1.output
  /bin/sh: flex scanner:command not found
  make *** [test] Error 127
  </code></pre>
  
  <p>What does this error mean?</p>