Linux hacks

Fluxbox

ClusterDuck

Jak pripojit 3, nebo 4 monitory k laptopu Lenovo T540p

#lspci
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller (rev 06)
00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)
...

interni + VGA + HDMI na dockine

#!/bin/bash
xrandr --output DP-1-3 --off
xrandr --output DP-1-2 --off
xrandr --auto
xrandr --output eDP-0 --left-of DP-1-2
xrandr --output DP-1-3 --left-of DP-1-2

#!/bin/bash
xrandr --output DP2-1 --off
xrandr --output DP2-2 --off
xrandr --output DP2-2 --mode 1920x1080 --right-of eDP1
xrandr --output DP2-1 --mode 1920x1080 --right-of DP2-2

interni + VGA + HDMI na dockine + USB

xrandr --output DVI-I-1 --mode 1280x1024 --left-of eDP1

screen

S

cat ~/bin/S
#!/bin/bash

if echo "$1" | grep '@' > /dev/null; then
        SSH_USER="$( echo "$1" | sed 's/\(@\).*/\1/' )"
        SSH_MACHINE="$( echo "$1" | sed 's/.*@//' )"
else
        if echo "$1" | grep '^#' > /dev/null; then
                SSH_USER="root@"
                SSH_MACHINE="$( echo "$1" | sed 's/^#//' )"
        elif echo "$1" | grep '^1' > /dev/null; then
                SSH_USER="user1@"
                SSH_MACHINE="$( echo "$1" | sed 's/^1//' )"
        elif echo "$1" | grep '^2' > /dev/null; then
                SSH_USER="user2@"
                SSH_MACHINE="$( echo "$1" | sed 's/^2//' )"
        else
                SSH_USER=""
                SSH_MACHINE="$1"

        fi
fi

# some machines can't be reached from outside simply, or must be reached by differrent ways
# from differrent places

DEFAULT_IFACE="$(/sbin/route -n | grep '^0.0.0.0' | sed 's/.* \([^ ]*\) *$/\1/')"
echo "Default route is going to: $DEFAULT_IFACE interface."
IP="$(/sbin/ifconfig "$DEFAULT_IFACE"|grep 'inet addr:'|sed 's/.*inet addr:\([0-9.]*\).*/\1/')"

if [ "$DEFAULT_IFACE" = 'ppp0' ]; then
        OUTSIDE=1
fi

if [ "$DEFAULT_IFACE" = 'eth0' ]; then
        if echo "$IP"|grep '192.168.1.' >/dev/null; then
                NET1=1
        elif echo "$IP"|grep '10.0.0.' >/dev/null; then
                NET2=1
        elif echo "$IP"|grep '192.168.2.' >/dev/null; then
                NET3=1
        else
                OUTSIDE=1
        fi
fi

if [ "$SSH_MACHINE" = 'machine1' ]; then
        if [ "$OUTSIDE" = '1' ]; then
                SSH_MACHINE='anothername.site.tld'
        fi
        if [ "$NET3" = '1' ]; then
                SSH_MACHINE='anothername.site.tld'
        fi
fi

if [ "$SSH_MACHINE" = 'anothername.site.tld' ]; then
        if [ "$NET1" = '1' ]; then
                SSH_MACHINE='machine1'
        fi
fi

# what should be on screen or xterm descr

if echo "$SSH_USER" | grep '^root@' > /dev/null; then
        TITLE_USER="#"
elif echo "$SSH_USER" | grep '^user1@' > /dev/null; then
        TITLE_USER="1"
elif echo "$SSH_USER" | grep '^user2@' > /dev/null; then
        TITLE_USER="2"
else
        TITLE_USER="$SSH_USER"
fi

if [ "$TERM" = 'screen' ]; then
        echo -ne "\033k$TITLE_USER$SSH_MACHINE\033\\"
elif [ "$TERM" = 'xterm' ]; then
        echo -ne "\033]0;$TITLE_USER$SSH_MACHINE\007"
else
        echo "SSH: $TITLE_USER$SSH_MACHINE"
fi

echo "user:$SSH_USER, machine:$SSH_MACHINE, iface:$DEFAULT_IFACE, ip:$IP, title:$TITLE_USER"

ssh -X "$SSH_USER$SSH_MACHINE"
     

bc

alias bc='bc -l ~/bin/bc_lib'

echo "alias bc='bc -l ~/bin/bc_lib'" >> ~/.bash_aliases

define as (x) { return a(x/sqrt(1-x^2)); }
define ac (x) { return a(sqrt(1-x^2)/x); }
define t (x) { return s(x)/c(x); }
# ^^ the library for arcsin, arccos and tan in radians
#pi=3.141592653589793238462643
pi=4*a(1)

#goniometric functions in degrees
rad2deg=180/pi
define sin (x) { return s(x/rad2deg); }
define cos (x) { return c(x/rad2deg); }
define tan (x) { return t(x/rad2deg); }
define asin (x) { return as(x)*rad2deg; }
define acos (x) { return ac(x)*rad2deg; }
define atan (x) { return a(x)*rad2deg; }

#decadic and binary logarithm
define log (x) { return l(x)/l(10); }
define lb (x) { return l(x)/l(2); }