RE: libpq debug log

Hi Iwata-san,

Currently, the patch fails to build according to CF app.
As you know, it has something to do with the misspelling of function.
GetTimezoneInformation --> GetTimeZoneInformation

It sounds more logical to me if there is a parameter that switches on/off the logging
similar to other postgres logs. I suggest trace_log as the parameter name.
Like, this parameter needs to be enabled for logdir, logsize and loglevel, etc. to work.
The default is off.

If you're going to introduce that parameter, then the docs should be updated as well.
i.e. "When trace_log is enabled, this parameter..."

How about changing the following parameter names:
logdir --> log_directory
logsize --> log_size
logminlevel --> log_min_level

If it's helpful, you might want to look into how the other postgres logs (i.e. syslogger)
allow setting either absolute or relative path for log directory, and how the parameters
cover some of the comments above by Ramanarayana.

Regards,
Kirk Jamison