-char devopn[] = "devopn";
-char devio[] = "devio";
-char devwait[] = "devwait";
-char devin[] = "devin";
-char devout[] = "devout";
-char devioc[] = "devioc";
-char devcls[] = "devcls";
+const char devopn[] = "devopn";
+const char devio[] = "devio";
+const char devwait[] = "devwait";
+const char devin[] = "devin";
+const char devout[] = "devout";
+const char devioc[] = "devioc";
+const char devcls[] = "devcls";