Question

When you use a system call in a Ruby script, you can get the output of that command like this:

output = `ls`
puts output

That’s what this question was about.

But is there a way to show the continuous output of a system call? For example, if you run this secure copy command, to get a file from a server over SSH:

scp user@someserver:remoteFile /some/local/folder/

… it shows continuous output with the progress of the download. But this:

output = `scp user@someserver:remoteFile /some/local/folder/`
puts output

… doesn’t capture that output.

How can I show the ongoing progress of the download from inside my Ruby script?

Answer 1

Try:

IO.popen("scp -v user@server:remoteFile /local/folder/").each do |fd|
  puts(fd.readline)
end