diff -up src/Net-Pcap-0.18/Pcap.xs.orig src/Net-Pcap-0.18/Pcap.xs
--- src/Net-Pcap-0.18/Pcap.xs.orig	2020-04-05 01:33:02.900000000 -0600
+++ src/Net-Pcap-0.18/Pcap.xs	2020-04-05 01:33:11.070000000 -0600
@@ -937,7 +937,7 @@ pcap_parsesrcstr(source, type, host, por
 
 pcap_t *
 pcap_open(source, snaplen, flags, read_timeout, auth, err)
-    char *source
+    const char *source
     int snaplen
     int flags
     int read_timeout