Description of problem:

I turned on tracing and directed the output to a log file. When I grepped the
file, grep said the file was binary. The "file" command said the log was "data"
instead of text. I found lines in the log for each connection that contained:

... ConnectionStartOkBody ... response=^@guest^@guest

The control character "^@" was preventing grep from listing all lines that
contained my pattern.
When I copied the log and edited out "^@", the grep worked as expected.


Additional info:

Debug logging outputs the beginning of message data without quoting control
characters. Control characters should be quoted in log output.