+.TP
+\fB\-d\fR, \fB\-\-debug\fR=\fILEVEL\fR
+set the debug level, integer between 0 and 3
+.TP
+\fB\-l\fR, \fB\-\-log\-file\fR=\fIPATH\fR
+set the log file to PATH
+.HP
+\fB\-\-sensor\-log\-file\fR=\fIPATH\fR set the sensor log file to PATH
+.HP
+\fB\-\-sensor\-log\-interval\fR=\fIS\fR set the sensor log interval to S (seconds)
+.SH "SENSOR LOG FILE"
+
+Sensors can be logged using the \-\-sensor-log-file option.
+
+It is using a text format, each line is terminated with a NEWLINE
+char.
+
+The first line is: I,%D,%V
+
+%D is the starting time of the log expressed as the number of seconds
+since EPOC.
+
+%V is the version of psensor-server.
+
+Following lines gives the ordered list of sensors: S,%I,%T
+
+%I is the uniq identifier of the sensor.
+
+%T is the hexadecimal representation of the sensor type.
+
+Then, the values of all sensors are written: %D,%V...
+
+%D is the number of seconds elapsed since the starting time of the
+log.
+
+%V... is the list separated by a comma of the current value of all
+sensors. The ordering is the same than the list of sensor identifiers.
+
+The value is expressed as a float with one digit precision. Temperatures
+are using Celsius unit.
+
+The value is written only if it has changed.
+
+Example:
+I,1345974927,0.7.0.4
+S,lmsensor coretemp-isa-0000 Physical id 0,101
+S,lmsensor coretemp-isa-0000 Core 0,101
+S,lmsensor coretemp-isa-0000 Core 1,101
+0,37.0,37.0,36.0
+5,36.0,,36.0
+
+Five seconds after the log starts, the temperature of the second
+sensor (Core 0) is still 37C.