Hello, I would like to know why
cmd = "/bin/df -H /dev/#{partition}"
used = `#{cmd}`

works fine but this fails
used = `"/bin/df -H /dev/#{partition}"`

with an OS error.

Thank you

BTW, is there an aliase to the backquote ? I mean a kernel method doing 
the same - Just for the syntax, backquotes are not very sexy.