Fix string buffer overflow when preparing the line of output.
Fix string buffer overflow when preparing the line of output.

PR:	bin/161739
Submitted by:	Jeremy Chadwick <freebsd jdc parodius com>
MFC after:	1 week

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase