When scripting in bash or any other shell in *NIX, while running a command that will take more than a few seconds, a progress bar is needed.
For example, copying a big file, opening a big tar file.
What ways do you recommend to add progress bars to shell scripts?
You can implement this by overwriting a line. Use \r
to go back to the beginning of the line without writing \n
to the terminal.
Write \n
when you're done to advance the line.
Use echo -ne
to:
\n
and\r
.Here's a demo:
echo -ne '##### (33%)\r'
sleep 1
echo -ne '############# (66%)\r'
sleep 1
echo -ne '####################### (100%)\r'
echo -ne '\n'
In a comment below, puk mentions this "fails" if you start with a long line and then want to write a short line: In this case, you'll need to overwrite the length of the long line (e.g., with spaces).