.TH THINKFAN "1" "June 2013" "thinkfan 0.9.1" "thinkfan"
.SH NAME
thinkfan \- A simple fan control program
.SH SYNOPSIS
.SY thinkfan
.OP \-hnqzDd
.OP \-b BIAS
.OP \-c CONFIG
.OP \-s SECONDS
.OP \-p [DELAY]
.YS
.SH DESCRIPTION
Thinkfan sets the fan speed according to temperature limits preconfigured in
\fI/etc/thinkfan.conf\fR. It can read temperatures from three possible
sources:
.IP "\fI/proc/acpi/ibm/thermal\fR"
Which is provided by the thinkpad_acpi kernel module,
.IP "\fI/sys/class/hwmon/*/temp*_input\fR"
Which may be provided by any hwmon drivers, and
.IP "\fIS.M.A.R.T.\fR (since 0.9)"
Which reads the temperature directly from the hard disk using libatasmart.
.P
Note that since 0.9 you can use any sensors of these three types at the same
time. To allow that, the configuration \fBkeywords\fR have been \fBchanged\fR. The
\fIsensor\fR keyword has been deprecated in favor of the new keywords
\fItp_thermal\fR, \fIhwmon\fR and \fIatasmart\fR which mark the following path
as a legacy thinkpad_acpi thermal file, sysfs hwmon file, or a hard disk
device file, respectively.
.P
The fan can be \fI/proc/acpi/ibm/fan\fR or some PWM file in \fI
/sys/class/hwmon\fR. Note that the \fIfan\fR config keyword is \fBdeprecated\fR as
well. Instead, you should use \fItp_fan\fR for a legacy thinkpad_acpi fan file
or \fIpwm_fan\fR for a sysfs PWM file.
.P
See the README file and the example configurations for details on these
changes.
.HP
\fBWARNING\fR: This program does only very basic sanity checking on the
configuration. That means that you can set your temperature limits as insane
as you like.
.P
There are two general modes of operation:
.SS COMPLEX MODE
In complex mode, temperature limits are defined for each sensor thinkfan knows
about. Setting suitable limits for each sensor in your system will probably
require a bit of experimentation and good knowledge about your hardware, but
it's the safest way of keeping each component within its specified temperature
range. See http://www.thinkwiki.org/wiki/Thermal_Sensors for details on
which sensor measures what temperature in a Thinkpad. On other systems you'll
have to find out on your own. See the example configs to learn about the
syntax.
.SS SIMPLE MODE
In simple mode, Thinkfan uses only the highest temperature found in the
system. That may be dangerous, e.g. for hard disks.  That's why you should
provide a correction value (i.e. add 10\-15 \°C) for the sensor that has the
temperature of your hard disk (or battery...). See the example config files
for details about that.
.SH CONFIGURATION
Some example configurations are provided with the source package. For detailed
explanations please read the README file. If you installed thinkfan from a
distribution package, you may find them under \fI/usr/share/doc\fR or wherever
your package manager puts documentation.
.SH OPTIONS
.TP
\fB\-h\fR
Show a short help message
.TP
\fB\-s\fR SECONDS
Maximum seconds between temperature updates (default: 5)
.TP
\fB\-b\fR BIAS
Floating point number (\-10 to 30) to control rising temperature exaggeration.
If the temperature increases by more than 2 °C during one cycle, this number
is used to calculate a bias, which is added to the current highest temperature
seen in the system:

 current_tmax = current_tmax + delta_t * BIAS / 10

This means that negative numbers can be used to even out short and sudden
temperature spikes like those seen on some on\-DIE sensors. Use DANGEROUS mode
to remove the \-10 to +30 limit. Note that you can't have a space between \-b
and a negative argument, because otherwise getopt will interpret things like
\-10 as an option and fail (i.e. write "\-b\-10" instead of "\-b \-10").

Default is 15.0
.TP
\fB\-c\fR FILE
Load a different configuration file (default: /etc/thinkfan.conf)
.TP
\fB\-n\fR
Do not become a daemon and log to terminal instead of syslog
.TP
\fB\-q\fR
Be quiet (no status info on terminal)
.TP
\fB\-z\fR
Assume we don't have to worry about resuming from standby when using the sysfs
interface (see README!)
.TP
\fB\-p\fR [SECONDS]
Use the pulsing\-fan workaround (for older Thinkpads). Takes an optional
floating\-point argument (0\-10s) as depulsing duration. Default 0.5s.
.TP
\fB\-d\fR
Do not read temperature from sleeping disks. Instead, 0 °C is used as that
disk's temperature. This is needed if reading the temperature causes your
disk to wake up unnecessarily.
\fBNote\fR: This option is only available if thinkfan was built with \-D USE_ATASMART.
.TP
\fB\-D\fR
DANGEROUS mode: Disable all sanity checks. May damage your hardware!!
.SH SIGNALS
SIGINT and SIGTERM simply interrupt operation and should cause thinkfan to
terminate cleanly.
.P
SIGHUP makes thinkfan reload its config. If there's any problem with the new
config, we keep the old one.
.P
SIGUSR1 causes thinkfan to dump all currently known temperatures either to
syslog, or to the console (if running with the \-n option).
.SH SEE ALSO
git://git.code.sf.net/p/thinkfan/code

.SH BUGS
If you have any problems with thinkfan, please go to the help forum at sf.net:
.RS
.RE
http://sourceforge.net/projects/thinkfan/forums/forum/905019.
.P
There's a bugtracker at
.RS
.RE
http://sourceforge.net/tracker/?group_id=249873&atid=2416828.