Print any number of stars and use font effects (dim, normal, bold) to give the effect of progress, goes from side to side

full-larson

#!/bin/bash

progWidth="${1:-3}"
sleepTime="0.2"

resetTerm() {
  tput sgr0     # Unset as many things that we've set as possible
  tput cnorm    # Display the cursor again
  printf '%s\n' ""
  exit 0
}

# Try to set things back the way they were, however we exit
trap resetTerm HUP INT QUIT TERM EXIT

# GNU sleep can handle fractional seconds, non-GNU cannot
# so we default to 1 second resolution in that scenario
if ! sleep "${sleepTime}" &>/dev/null; then
  sleepTime=1
fi

tput sc                                    # Capture position
tput civis                                 # Hide cursor
tput dim                                   # Set base emphasis
printf '%*s' "${progWidth}" | tr ' ' "*"   # Setup base char width
while true; do                             # Infinite loop
  tput rc                                  # Return to saved position
  for ((i=0;i<progWidth;i++)); do          # Iterate horizontally
    for em in dim sgr0 bold sgr0 dim; do   # Emphasis sequence
      printf -- '%s' "$(tput "${em}")*"    # Output emphasised char
      sleep "${sleepTime}"                 # Pause for effect
      tput cub1                            # Move left one char
    done
    tput cuf1                              # Move right one char
  done
  tput cub1
  for ((i=progWidth;i>0;i--)); do
    for em in dim sgr0 bold sgr0 dim; do
      printf -- '%s' "$(tput "${em}")*"
      sleep "${sleepTime}"
      tput cub1
    done
    tput cub1
  done
done