vmstat reports information about processes, memory, paging, block IO, traps, disks and cpu activity.

the output is like this

procs ------memory------- --swap-- ---io--- -system-- ----cpu----
 r b swpd free buff cache  si  so   bi   bo  in    cs   us sy id  wa
 0 0  0   9999 9999 9999    0   0   99   99  9999  999  9  9  99  9

[download]

Let's see...

Your target is the 13th number in the third line, so you need to discard lines 1 and 2, and then print this element

my @stat = `vmstat`;
foreach $line(@stat){
    if ($line =~ /^procs/){next}
    if ($line =~ /us/){next}
    else {chomp $line;
          my @fo = split /[[:blank:]]+/, $line;
          print "Message: CPU user time: $fo[13]\n";}
}

[download]

In reply to Re^2: returning a specific value from a command by pvaldes
in thread returning a specific value from a command by familyofcrowes

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.