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git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@34767 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/curses/curses.c

@@ -2769,14 +2769,17 @@ Init_curses(void)
     rb_define_module_function(mCurses, "reset_prog_mode", curses_reset_prog_mode, 0);
 
 #if defined(HAVE_FUNC_CURSES_VERSION)
+    /* ncurses and PDcurses */
     rb_define_const(mCurses, "VERSION", rb_str_new2(curses_version()));
 #elif defined(HAVE_VAR_CURSES_VERSION)
     {
-        /* SVR4 curses has an undocumented and undeclared variable, curses_version. */
+        /* SVR4 curses has an undocumented and undeclared variable, curses_version.
+         * It contains a string, "SVR4".  */
         RUBY_EXTERN char *curses_version;
         rb_define_const(mCurses, "VERSION", rb_sprintf("curses (%s)", curses_version));
     }
 #else
+    /* BSD curses, perhaps.  NetBSD 5 still use it. */ 
     rb_define_const(mCurses, "VERSION", rb_str_new2("unknown"));
 #endif