diff --git a/database/DBlabel.c b/database/DBlabel.c
index 388c9da6..1766496d 100644
--- a/database/DBlabel.c
+++ b/database/DBlabel.c
@@ -1549,7 +1549,7 @@ DBLoadFont(fontfile, scale)
     float scale;
 {
     FILE *ff;
-    char *ascii_names[] = {
+    const char * const ascii_names[] = {
 	"space", "exclam", "quotedbl", "numbersign", "dollar",
 	"percent", "ampersand", "quoteright", "parenleft", "parenright",
 	"asterisk", "plus", "comma", "hyphen", "period", "slash", "zero",
@@ -1654,7 +1654,7 @@ DBLoadFont(fontfile, scale)
 	    {
 		if (psname != NULL)
 		{
-		    asciiidx = LookupStructFull(psname, ascii_names, sizeof(char *));
+		    asciiidx = LookupStructFull(psname, ascii_names, sizeof(const char *));
 		    if (asciiidx >= 0)
 			chardef = 2;
 		}
diff --git a/textio/txInput.c b/textio/txInput.c
index 7a22eafb..3a6ef16d 100644
--- a/textio/txInput.c
+++ b/textio/txInput.c
@@ -105,11 +105,11 @@ char *magic_direction_list[] = {
 #define DIRECT_COMPL  10
 
 /* Can only accommodate 32 arg options, increase as necessary */
-static struct cmd_spec {
-  char *cmd;
+static const struct cmd_spec {
+  const char *cmd;
   int   type;
   char *args[32];
-} magic_cmd_spec[] = {
+} const magic_cmd_spec[] = {
   { "", COMMAND_COMPL, {(char *)NULL} },
   { "help", COMMAND_COMPL, {(char *)NULL} },
 
@@ -595,13 +595,13 @@ magic_completion_function(char *text, int start, int end)
 		strcat(line, " ");
 	}
 
-	entry = LookupStructFull(line, (char **)&magic_cmd_spec,
+	entry = LookupStructFull(line, (const char * const *)&magic_cmd_spec,
 		sizeof(struct cmd_spec));
 
 	if (entry == -1 && num_tokens >= 1)
 	{
 	    sprintf(line, "%s*", tokens[0]);
-	    entry = LookupStructFull(line, (char **)&magic_cmd_spec,
+	    entry = LookupStructFull(line, (const char * const *)&magic_cmd_spec,
 			sizeof(struct cmd_spec));
 	}