dde826b6f5
In some cases, the required information is not available and the UDP provider reported an empty string in this case and the IP and TCP provider reported a NULL pointer. This patch changes the value provided in this case to the string "<unknown>". This make the behaviour consistent and in-line with the behaviour of Solaris. Reviewed by: markj@, dteske@, gnn@ Differential Revision: https://reviews.freebsd.org/D15855