title: Retrive host name from environment variable DISPLAY in Makefile
body: <p>Suppose my environment variable DISPLAY is "mypc:0.0", how could I retrieve the hostname part "mypc" in a Makefile?</p>
  
  <p>I have tried something like 
  <code>@echo $(patsubst :0.0,,$(DISPLAY))</code>
  without any luck.</p>
  
  <p>Thanks in advance.</p>