Shell Programming and Scripting

#!/bin/sh

# progbar3.sh
# Simulate a progress bar with colors
# Author: Sofiane Cherchalli
# Date: 24 Oct 2010

dot="."
a=( '/' '-' '\' '|' )
per=0

do_sleep() {
  local t="$1"
  which perl &>/dev/null && sleep_cmd="perl -e 'select(undef,undef,undef,$t)'" || sleep_cmd="sleep $t"
  eval "$sleep_cmd"
}

wait_4_esc() {
  local msg="Please, press two times ESC key to start demo: "
  while read -s -n2 -p "$msg" key; do
    printf "\n"
    [ "$key" = "`echo $'\x1b\x1b'`" ] && break || msg="What??? I said Press TWO TIMES ESC key on your keyboard to start demo!. Is my english that bad? :( . Try again: "
  done
}

# main
wait_4_esc
printf "\nThanks! :) . Starting demo right now...\n"
while [ "$per" -le "100" ]; do
  showper=`expr $per % 10`
  if [ "$showper" = "0" ]; then
    if [ "$per" -le "30" ]; then
      printf "\e[31m%s" "${per}%"
    elif [ "$per" -gt "30" -a "$per" -le "70" ]; then
      printf "\e[33m%s" "${per}%"
    else
      printf "\e[32m%s" "${per}%"
    fi
  fi

  for ((i=0; i<${#a[@]}; i++)); do
    printf "\e[0m%s" "${a[${i}]}"
    do_sleep .1
    printf "\e[1D\e[0K"
  done

  [ "$per" -lt "100" ] && printf "\e[0m%s" "$dot"
  per=`expr $per + 1`
done
printf "\e[0m\nHYLI!\n\n"

#!/bin/sh

# progbar6.sh
# Simulate a progress bar with colors
# Author: Sofiane Cherchalli
# Date: 24 Oct 2010


do_sleep() {
  local t="$1"
  which perl &>/dev/null && sleep_cmd="perl -e 'select(undef,undef,undef,$t)'" || sleep_cmd="sleep $t"
  eval "$sleep_cmd"
}

show_prog_bar() {
  local c="$1" # Character to use to draw progress bar
  local v=$2 # Percentage 0<= value <=100

  local pbl=50 # Progress bar length in characters
  local r=`expr 100 / $pbl` # Ratio between percentage value and progress bar length
  local p="$v%" # Percentage value to display in the middle of progress bar
  local l=${#p} # Length of string to display
  local pbs="" # Progress bar string
  local k=`expr \( $pbl - $l \) / 2` # Position where to substitute in progress bar string
  local n1=`expr $v / $r`
  local n2=`expr $pbl - $n1`

  for (( i=0; i<$pbl; i++ )); do
    pbs="${pbs}${c}"
  done

  pbs=`echo "$pbs" | sed 's/^\(.\{'"${k}"'\}\)\(.\{'"${l}"'\}\)\(.*$\)/\1'"${p}"'\3/'`

  printf "\r\e[44m%s\e[41m%s" "${pbs:0:$n1}" "${pbs:$n1:$n2}"
}

# Simulate a child process doing some work. Progress percentage is wtitten to a temp file
some_work() {
  local a=(0 3 5 20 37 51 67 80 98 100) # Simulate some progress values done by worker
  local sl=(1 .3 .5 3 .5 .9 1 .8 1 3) # Simulate some work times

  for ((i=0; i<${#a[@]}; i++)); do
    echo "${a[${i}]}" >> /tmp/progbar
    do_sleep ${sl[${i}]}
  done
}

wait_4_esc() {
  local msg="Please, press two times ESC key to start demo: "
  while read -s -n2 -p "$msg" key; do
    printf "\n"
    [ "$key" = "`echo $'\x1b\x1b'`" ] && break || msg="What??? I said Press TWO TIMES ESC key on your keyboard to start demo!. Is my english that bad? :( . Try again: "
  done
}

# main
wait_4_esc
> /tmp/progbar

some_work &
pid=$!

per=0
printf "\nThanks! :) . Starting demo right now...\n"
while read line || [ "$per" -lt "100" ]; do
  if [ -n "$line" ]; then
    per=$line
    show_prog_bar " " $per
  fi
  do_sleep .1
done < /tmp/progbar

printf "\e[0m\nHYLI!\n\n"