dns plugin: Fix a compile warning.

diff --git a/src/dns.c b/src/dns.c
index bf341a7..74fab98 100644 (file)
--- a/src/dns.c
+++ b/src/dns.c
@@ -182,7 +182,7 @@ static void dns_child_callback (const rfc1035_header_t *dns)
                int skip = 0;
                if (!select_numeric_qtype)
                {
-                       char *str = qtype_str(dns->qtype);
+                       const char *str = qtype_str(dns->qtype);
                        if ((str == NULL) || (str[0] == '#'))
                                skip = 1;
                }