Shell Programming and Scripting

#!/bin/bash

progress_bar()
{

(
while :
do

# =================================================================
echo "# Uploading" ; sleep 2
echo "25"
echo "# Uploading" ; sleep 2
echo "50"
echo "# Uploading" ; sleep 2
echo "75"
echo "# Uploading" ; sleep 2
echo "99"
echo "# Uploading" ; sleep 2
done

)  |
`zenity --progress  --title="Progress Status"  --auto-close  --auto-kill 2>&1`
a=111
echo $a
(( $? != 0 )) && zenity --error --text="Error in zenity command."

exit 0
}

while :
do
  progress_bar &  `curl  -o "bigfile222"    <downloadurl> 2>/dev/null`

wait $(jobs -p)
done
exit
~

curl -o filename http://website/file 2>&1 |
        awk -v RS="\r" 'BEGIN { print "# Downloading file" } ; $1 ~ /[0-9]/ { print $1 }' | zenity --progress

wget -O - "${source_url}" | pv options > ${target_file}

:

target_file=/path/to/your/file
expected_size=1024000000           # Estimate on the file size
:
:
while :
do
   sleep 2
   current_size=$(stat -c %s ${target_file})
   ((percent_complete=(${current_size}*100)/${expected_size}))
   printf "\rDownload is %2.0d\% complete."
done &                 #   Loop in the background
bg_process_id=$!       # Get the process id of the background loop

curl -o "${target_file}" "${source_url}"
kill $bg_process_id