How to add a progress bar to a shell script?

Question

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 b

Answer 1

Many answers describe writing your own commands for printing out '\r' + $some_sort_of_progress_msg. The problem sometimes is that printing out hundreds of these updates per second will slow down the process.

However, if any of your processes produce output (eg 7z a -r newZipFile myFolder will output each filename as it compresses it) then a simpler, fast, painless and customisable solution exists.

Install the python module tqdm.

$ sudo pip install tqdm
$ # now have fun
$ 7z a -r -bd newZipFile myFolder | tqdm >> /dev/null
$ # if we know the expected total, we can have a bar!
$ 7z a -r -bd newZipFile myFolder | grep -o Compressing | tqdm --total $(find myFolder -type f | wc -l) >> /dev/null

Help: tqdm -h. An example using more options:

$ find / -name '*.py' -exec cat \{} \; | tqdm --unit loc --unit_scale True | wc -l

As a bonus you can also use tqdm to wrap iterables in python code.

https://github.com/tqdm/tqdm/blob/master/README.rst#module