Ubuntu fix dual monitor reboot

backup bash filez

#!/bin/bash
# -------------------------------------------------
#  Get monitors configuration from monitor.xml and apply it for current user session.
#  In case of multiple definitions in monitor.xml only first one is used.
#
#  See http://bernaerts.dyndns.org/linux/74-ubuntu/309-ubuntu-dual-display-monitor-position-lost
#  for instructions
#
#  Revision history :
#    19/04/2014, V1.0 - Creation by N. Bernaerts
#    10/07/2014, V1.1 - Wait 5 seconds for X to fully initialize
#    30/07/2014, V1.2 - K. Callenberg added handling of primary monitor setting
# -------------------------------------------------


# get number of declared monitors
NUM=$(xmllint --xpath 'count(//monitors/configuration['1']/output)' $HOME/.config/monitors.xml)

# loop thru declared monitors to create the command line parameters
for (( i=1; i<=$NUM; i++)); do
  # get attributes of current monitor (name and x & y positions)
  NAME=$(xmllint --xpath 'string(//monitors/configuration['1']/output['$i']/@name)' $HOME/.config/monitors.xml 2>NULL)
  POS_X=$(xmllint --xpath '//monitors/configuration['1']/output['$i']/x/text()' $HOME/.config/monitors.xml 2>NULL)
  POS_Y=$(xmllint --xpath '//monitors/configuration['1']/output['$i']/y/text()' $HOME/.config/monitors.xml 2>NULL)
  PRIMARY=$(xmllint --xpath '//monitors/configuration['1']/output['$i']/primary/text()' $HOME/.config/monitors.xml 2>NULL)

  # if position is defined for current monitor, add its position to command line parameters
  if [ "$PRIMARY" == "yes" ] ; then
      [ -n "$POS_X" ] && PARAM_ARR=("${PARAM_ARR[@]}" "--output" "$NAME" "--primary" "--pos" "${POS_X}x${POS_Y}")
  else
      [ -n "$POS_X" ] && PARAM_ARR=("${PARAM_ARR[@]}" "--output" "$NAME" "--pos" "${POS_X}x${POS_Y}")
  fi
done

# wait for 5 seconds (for X to finish initialisation)
sleep 5

#echo "${PARAM_ARR[@]}"

# position all monitors
xrandr "${PARAM_ARR[@]}"

gistfile1.md

1. rm ~/.config/monitors.xml && gnome-control-center
2. setup displays
3. sudo apt-get install libxml2-utils
4. sudo wget -O /usr/local/sbin/update-monitor-position http://www.calgorithms.com/assets/files/update-monitor-position && sudo chmod +x /usr/local/sbin/update-monitor-position
5. System - Startup Applications tool > update-monitor-position