more efficient regex to parse linux top command values

Tag: regex,linux,perl,optimization

I'm trying to grab some measurements on a per process level in this script I'm writing. The easiest way to see the values I'm looking for is to just grab the output of the top command.

So when I try to parse it though, my regex looks kind of ridiculous. Given this output:

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 8364 cgroup_t  20   0  764m 646m 1520 R 101.7  4.3   0:05.51 perl

I came up with the regex to grab some values(the 8364 is passed in on a var and shown here for ease of reading and the top output is stored on a var called $top_string):

if($top_string =~ m/^\s*8364\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)\s+([^\s]+)/){
    #return desired var number, ie.  $1,$2...etc
}

This works but it seems like overkill. Is there any way to do this more efficiently? I feel like maybe I remember a way to avoid typing the \s+([^\s]+) pattern over and over.

Anyway thanks for taking the time to read this!

Cheers

Best How To :

use split when you have delimiter

my @cols = split ' ', ( $top_string =~ /(\d.+)/ )[0];

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