change Pulseaudio volume from command line. BE CAREFUL: Setting the volume higher than 150% may harm your device or speakers!

volume

#!/bin/bash

CRITICAL_LIMIT=153
SINK=1

input="$@"
new_vol=0


function usage {
  echo "Usage: $(basename $0) [+/-]INT"
  echo "    INT: absolute value or relative (with leading +/-)"
}

function get_sink_volume {
    SINK_NO=$1
    sink_vol=$(pactl list sinks | sed -n -e "/Sink #$SINK_NO/,\$p" | grep '^\sVolume: ' | awk '{print $5}')
    sink_vol=${sink_vol%"%"}
    echo $sink_vol
}

function get_relative_volume {
    SINK_NO=$1
    cur_vol=$2
    change=${input:0:1}" "${input:1}
    new_vol=$(expr $cur_vol $change)
    if [[ new_vol -gt 0 ]]; then new_vol=0; fi
    echo $new_vol
}

if [[ -z $input ]]; then
    echo "Current Volume: $(get_sink_volume $SINK)%"
fi

if ! [[ $input =~ ^[-|+]?[0-9]+$ ]]; then
    usage
    exit
fi


cur_vol=$(get_sink_volume $SINK)

if [[ $input =~ ^[-|+] ]]; then
    # Relative input:
    new_vol=$(get_relative_volume $SINK $cur_vol)
    echo "Current volume: $cur_vol%. New Volume: $new_vol%"
else
    # Absolute Input
    new_vol=$input
fi

ask=$(expr $new_vol /  150)
if [[ $cur_vol -lt $new_vol ]] && [[ $new_vol -gt $CRITICAL_LIMIT ]]; then
  while true; do
    read -p "$new_vol%?: Are you sure?" yn
    case $yn in
      [Yy]* ) if [[ $ask -gt 1 ]]; then ask=$(expr $ask - 1); echo "Really? Answer 'y' $ask more times!"; continue;
              else  echo "okay!"; break
              fi
            ;;
      [Nn]* ) echo "canceled"; exit;;
      * ) echo "Please answer yes or no.";;
    esac
  done
fi

VOL=$(expr $new_vol \* 65536 / 100)
echo "setting volume to $new_vol% ($VOL)"
pacmd set-sink-volume $SINK $VOL