*** ./install	Sun Jan 18 09:56:11 2004
--- ./install	Fri Apr  2 09:54:56 2004
***************
*** 156,161 ****
--- 156,175 ----
                          test_proceed;
                  fi; 
          done;
+ 
+         echo -n "Checking for diff... ";
+         diff -v 2>&1 | grep -iv "not found" >/dev/null 2>&1;
+         if [ "$?" -eq "0" ]; then
+                 echo "ok";
+         else
+                 echo "NO!";
+                 echo "";
+                 echo "diff is not present on your system.";
+                 echo "";
+                 echo "Please install it using Cygwin's setup.exe";
+                 echo "before trying to install the ns-2 distribution.";
+                 test_proceed;
+         fi;     
  }
  
  # Package VERSIONs. Change these when releasing new packages
***************
*** 172,178 ****
  CUR_PATH=`pwd`
  
  # A Cygwin install requires these packages:
! packages="gcc gcc-g++ gawk tar gzip make diff patch perl w32api\
             XFree86-base XFree86-bin XFree86-prog XFree86-lib XFree86-etc";
  
  # Check if we are using Cygwin, and if so, if it is a good install
--- 186,192 ----
  CUR_PATH=`pwd`
  
  # A Cygwin install requires these packages:
! packages="gcc gcc-g++ gawk tar gzip make patch perl w32api\
             XFree86-base XFree86-bin XFree86-prog XFree86-lib XFree86-etc";
  
  # Check if we are using Cygwin, and if so, if it is a good install
