-.TH "BREEZED" "1"
-.SH "NAME"
+.TH "BREEZED" "1"
+.SH "NAME"
breezed - Fan control daemon
-.SH "SYNOPSIS"
-.PP
-\fBbreezed\fP [\fBoptions\fP]
-.SH "DESCRIPTION"
-.PP
-\fBbreezed\fP
-Adjusts the fan speed according to the temperature of the computer.
-.SH "OPTIONS"
-.IP "\fB-h | --help\fP " 10
+.SH "SYNOPSIS"
+.PP
+\fBbreezed\fP [\fBoptions\fP]
+.SH "DESCRIPTION"
+.PP
+\fBbreezed\fP is a daemon to adjust the fan speed according to the
+computer temperature. It should be started through the adequate script
+in /etc/rc?.d.
+
+Every 5s, \fBbreezed\fP gathers all integer values from the thermal
+files, and takes the max as the overall temperature T. It then
+computes the highest fan speed whose temperature threshold is lower
+than T. If that speed is above the current speed, the daemon changes
+the fan speed accordingly. Otherwise it computes the lowest fan speed
+whose temperature threshold is two degrees above T, and sets the fan
+speed one level below. This two degree gap avoids too many
+oscillations. Also, the daemon waits for at least 30s after any change
+of the fan speed before reducing it. The fan speed is set by writing
+"level <level>" into the specified fan file.
+
+Options can not be specified twice, neither on the command line nor in
+the configuration file.
+
+.SH "OPTIONS"
+.IP "\fB-h | --help\fP" 10
display help and exits
-.IP "\fB-v | --version\fP " 10
+.IP "\fB-v | --version\fP" 10
display the version number and exits
-.IP "\fB-d | --debug\fP " 10
+.IP "\fB-d | --debug\fP" 10
run in verbose mode
-.IP "\fB-cf | --configuration-file <file>\fP " 10
+.IP "\fB-cf | --configuration-file <file>\fP" 10
set the configuration file (default is /etc/breezed.conf)
-.IP "\fB-ncf | --no-configuration-file\fP " 10
+.IP "\fB-ncf | --no-configuration-file\fP" 10
prevent the reading of a configuration file
-.IP "\fB-tf | --thermal-file <file1>[,file2]...\fP " 10
+.IP "\fB-tf | --thermal-file <file1>[,file2]...\fP" 10
set the files to spool for temperatures.
-.IP "\fB-ff | --fan-file <file>\fP " 10
+.IP "\fB-ff | --fan-file <file>\fP" 10
set the file to control the fan speed.
-.IP "\fB-tt | --temperature-thresholds <temp1>[,temp2]...\fP " 10
+.IP "\fB-tt | --temperature-thresholds <temp1>[,temp2]...\fP" 10
set the temperature thresholds.
-.SH "AUTHOR"
-.PP
+.SH "CONFIGURATION FILE"
+
+The configuration file is a succession of lines, each starting with
+one of the three keywords thermal_files, fan_file or
+temperature_thresholds, followed by the same parameter values as for
+the command line arguments. The default configuration file is located
+at /etc/breezed.conf
+
+.SH "EXAMPLES"
+
+A typical way of starting breezed is
+
+breezed --thermal-files /proc/acpi/thermal_zone/THM0/temperature,/proc/acpi/thermal_zone/THM1/temperature \
+ --fan-file /proc/acpi/ibm/fan \
+ --temperature-thresholds 52,54,56,58,60,62,64
+
+which specifies that when the temperature raises above 52C, the fan
+level should be 1, when the temperature raises above 54C it should be
+2, etc. The maximum speed level 7 should be chosen for temperature
+above 64C. Due to the two degrees gap between the thresholds to
+increase and thresholds to decrease the temperature, it will for
+instance remains at speed 1 until the temperature goes down to 50C.
+
+Because it takes into account all the values found in the thermal
+files, you can use as well /proc/acpi/thermal_zone/THM?/temperature or
+/proc/acpi/ibm/thermal.
+
+.SH "AUTHOR"
+.PP
Written by Francois Fleuret <francois@fleurer.org>. Permission is
granted to copy, distribute and/or modify this document under the
terms of the GNU GPL.