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$ cat /etc/hostname

devmini 

$ cat /etc/hosts

127.0.0.1       localhost

127.0.1.1       devmini

# The following lines are desirable for IPv6 capable hosts

::1     ip6-localhost ip6-loopback

fe00::0 ip6-localnet

ff00::0 ip6-mcastprefix

ff02::1 ip6-allnodes

ff02::2 ip6-allrouters 

$ iwconfig --help

Usage: iwconfig [interface]

                interface essid {NNN|any|on|off}

                interface mode {managed|ad-hoc|master|...}

                interface freq N.NNN[k|M|G]

                interface channel N

                interface bit {N[k|M|G]|auto|fixed}

                interface rate {N[k|M|G]|auto|fixed}

                interface enc {NNNN-NNNN|off}

                interface key {NNNN-NNNN|off}

                interface power {period N|timeout N|saving N|off}

                interface nickname NNN

                interface nwid {NN|on|off}

                interface ap {N|off|auto}

                interface txpower {NmW|NdBm|off|auto}

                interface sens N

                interface retry {limit N|lifetime N}

                interface rts {N|auto|fixed|off}

                interface frag {N|auto|fixed|off}

                interface modulation {11g|11a|CCK|OFDMg|...}

                interface commit

       Check man pages for more details.

$ iwconfig

wlan0     IEEE 802.11bgn  ESSID:off/any

          Mode:Managed  Access Point: Not-Associated   Tx-Power=20 dBm

          Retry short limit:7   RTS thr:off   Fragment thr:off

          Power Management:off

lo        no wireless extensions.

eth0      no wireless extensions.

eth0      no wireless extensions. 

#! /bin/sh

### BEGIN INIT INFO

# Provides:          ondemand

# Required-Start:    $remote_fs $all

# Required-Stop:

# Default-Start:     2 3 4 5

# Default-Stop:

# Short-Description: Set the CPU Frequency Scaling governor to "ondemand"

### END INIT INFO

PATH=/sbin:/usr/sbin:/bin:/usr/bin

. /lib/init/vars.sh

. /lib/lsb/init-functions

case "$1" in

    start)

        start-stop-daemon --start --background --exec /etc/init.d/ondemand -- background

        ;;

    background)

        sleep 60 # probably enough time for desktop login

        for CPUFREQ in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

        do

                [ -f $CPUFREQ ] || continue

                echo -n ondemand > $CPUFREQ

        done

        ;;

    restart|reload|force-reload)

        echo "Error: argument '$1' not supported" >&2

        exit 3

        ;;

    stop)

        ;;

    *)

        echo "Usage: $0 start|stop" >&2

        exit 3

        ;;

esac 

$ ls -al /sys/devices/system/cpu/cpu*/cpufreq/

/sys/devices/system/cpu/cpu0/cpufreq/:

합계 0

drwxr-xr-x 4 root root    0 2015-02-12 17:34 .

drwxr-xr-x 7 root root    0 2015-02-12 17:32 ..

-r--r--r-- 1 root root 4096 2015-02-12 17:43 affected_cpus

-r-------- 1 root root 4096 2015-02-12 17:43 cpuinfo_cur_freq

-r--r--r-- 1 root root 4096 2015-02-12 17:33 cpuinfo_max_freq

-r--r--r-- 1 root root 4096 2015-02-12 17:43 cpuinfo_min_freq

-r--r--r-- 1 root root 4096 2015-02-12 17:43 cpuinfo_transition_latency

drwxr-xr-x 2 root root    0 2015-02-12 17:43 ondemand

-r--r--r-- 1 root root 4096 2015-02-12 17:43 related_cpus

-r--r--r-- 1 root root 4096 2015-02-12 17:33 scaling_available_frequencies

-r--r--r-- 1 root root 4096 2015-02-12 17:43 scaling_available_governors

-r--r--r-- 1 root root 4096 2015-02-12 17:34 scaling_cur_freq

-r--r--r-- 1 root root 4096 2015-02-12 17:43 scaling_driver

-rw-r--r-- 1 root root 4096 2015-02-12 17:34 scaling_governor

-rw-r--r-- 1 root root 4096 2015-02-12 17:33 scaling_max_freq

-rw-r--r-- 1 root root 4096 2015-02-12 17:43 scaling_min_freq

-rw-r--r-- 1 root root 4096 2015-02-12 17:43 scaling_setspeed

drwxr-xr-x 2 root root    0 2015-02-12 17:43 stats 

$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_available_governors

conservative ondemand userspace powersave performance 

LD_SHOW_AUXV

              (glibc since 2.1) Show auxiliary array passed up from the

              kernel.  For security reasons, since glibc 2.3.5, LD_SHOW_AUXV

              is ignored for set-user-ID/set-group-ID binaries.

[링크 : http://man7.org/linux/man-pages/man8/ld.so.8.html]