CURL Progress Bar: How to pipe and extract numbers only using grep?

Question

This is what I have so far:

[my1@graf home]$ curl -# -o f1.flv 'http://osr.com/f1.flv' |  grep -o '*[0-9]*'
####################################################################### 100.0%

I wish to use grep and only extract the percentage from that progress bar that CURL outputs.

I think my regex is not correct and I am also not sure if this grep will take effect of the the percentage being continuously updated?

What I am trying to do is basically get CURL only to give me the percentage number as the output and nothing else.

Thank you for any help.

Answer 1

You need to use .* not * in your regex.

grep -o '.*[0-9].*'

That will catch all text though, so maybe try:

grep -p '[0-9]+'

Answer 2

You can't get the progress info like that through grep; it doesn't make sense.

curl writes the progress bar to stderr, so you have to redirect to stdout before you can grep it:

$ curl -# -o f1.flv 'http://osr.com/f1.flv' 2>&1 | grep 1 | less results in:

^M                                                                           0.0
%^M######################################################################## 100.
0%^M######################################################################## 100
.0%^M######################################################################## 10
0.0%

Are you expecting a continual stream of numbers that you are redirecting somewhere else? Or do you expect to grab the numbers at a single point?

If it's the former, this sort of half-assedly works on a small file:

$ curl -# -o f1.flv 'http://osr.com/f1.flv' 2>&1 | sed  's/#//g' -
 100.0%                                                                    0.0%

But it's useless on a large file. The output doesn't print until the download is finished, probably because curl seems to be sending ^H's to the terminal. There might be a better way to sed it, but I wouldn't hold my breath.

$ curl -# -o l.tbz 'ftp://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2009/06/2009-06-02-05-mozilla-1.9.1/firefox-3.5pre.en-US.linux-x86_64.tar.bz2' 2>&1 | sed 's/#//g' -
 100.0%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%