-extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c,
- const Config *cfg);
-extern char *pfd_addforward(char *desthost, int destport, char *srcaddr,
- int port, void *backhandle, const Config *cfg);
+extern const char *pfd_newconnect(Socket * s, char *hostname, int port,
+ void *c, const Config *cfg);
+/* desthost == NULL indicates dynamic (SOCKS) port forwarding */
+extern const char *pfd_addforward(char *desthost, int destport, char *srcaddr,
+ int port, void *backhandle,
+ const Config *cfg);