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+====== Makefiles ======
+Makefiles are command files used by the "make" or "gmake" system to create a software system (or sometimes other object, such as documentation) from sources.
+The important thing for //users// to remember is\\
+== Never Execute a Makefile ==
+The syntax is fairly different from shell or other scripts; nevertheless, it occurs surprisingly often that a shell interpreter is able to 'interpret' the first few lines of a makefile. If, as often occurs, the first template happens to be one for uninstalling the package, the results can be disastrous. For example, if the variables $dir, $base and $ext haven't been initialised in a way the shell can understand, then
+  rm $dir/$base*$ext
+might well get interpreted as
+  rm /*
+======  ======
+The important thing for //developers// to remember is\\
+== Always protect Users from Executing a Makefile ==
+For the reasons above, I strongly recommend, if you are writing a makefile, to include as early as possible in your file something like:
+  # Template to protect users against accidentally
+  # executing a makefile - skipped if called by make
+  # if called as a script,
+  # it should barf on the unexpected "ifeq",
+  # but even if it manages to ignore that,
+  # it should print and exit
+  # Note that this protection is needed, because makefiles
+  # can sometimes be valid shell scripts - witness the
+  # standard XMILL makefile that manages to skip errors
+  # till it gets to
+  # clean:
+  #	rm -r -f $(TMP)/* $(TARGETS)
+  # when executed in most unix shells -
+  # which isn't very nice if $(TMP) is undefined...
+  ifeq (1,0)
+    echo "THIS IS NOT A SHELL SCRIPT!!!!"
+    echo "IT IS A CONFIGURATION FILE FOR THE make SYSTEM"
+    echo "DO NOT EXECUTE IT"
+    exit 1
+  endif
+This won't affect the execution of the makefile at all, because 1 will never equal 0 (so the nested part will never even be seen by make)
+It works as a protection in all unix shells I have tried; it may not work as well in DOS, but I assume it would at least cause an abort.

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