diff --git a/src/option.c b/src/option.c
index 4d12834..7cac89e 100644
--- a/src/option.c
+++ b/src/option.c
@@ -7697,7 +7697,7 @@
 	{
 	    for (opt_idx = 0; (str = get_termcode(opt_idx)) != NULL; opt_idx++)
 	    {
-		if (!isprint(str[0]) || !isprint(str[1]))
+		if (!SAFE_isprint(str[0]) || !SAFE_isprint(str[1]))
 		    continue;
 
 		name_buf[0] = 't';