From: Ken Bloom <kbloom@...>
Date: 2009-12-24T10:08:37+09:00
Subject: Re: awk print $4 in ruby

On Wed, 23 Dec 2009 13:12:11 +0900, Derek Smith wrote:

> Hi All,
> 
> I had played in Ruby a while and could not get this to work.
> 
> df -m
> Filesystem             1M-blocks Used Avail Capacity  Mounted on
> /dev/concat/v109-v112a      7931 2619  4677    36%    /
> 
> [root@vr /usr/local/vrep/OS_scripts]# df -k |awk '{print $4}' Avail
> 4789776
> 
> dfstr = Array.new
> dfstr << %x(df -m)
> dfstr.each do |line|
>     puts line if line =~ /(\d+)%/
> end
> 
> Since its one line, it of course prints it all. I then tried:
> 
> dfstr.each do |line|
>     puts line.split[3]
> end
> 
> And it only prints "Avail"
> 
> I then tried:
> 
> puts dfstr.scan(/Avail.*/)
> 
> and
> 
> puts dfstr.split(/\d+/)[3]
> 
> with NO success.
> 
> Goal is to get certain data columns such as Used Avail Capacity.
> 
> thank you!

dfstr = %x(df -m)
dfstr.each do |line|
  puts line.split[3]
end

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-- 
Chanoch (Ken) Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/