I have tried assigning value of SHELL command to PERL variable by using back ticks as well as qx{} but still I am not able to assign the output of the SHELL COMMAND to a PERL variable. I tried working with system and exec though knowing that they assign exit status. Nothing is working hence anyone who could help. You will see ssh in code and it is passwordless so not a problem. The SHELL COMMAND is working properly on command prompt The SHELL COMMAND basically tries to get the status of service on other node where the service would be running or stopped 


my $status = qx{ssh r01mn1 /etc/init.d/hadoop-0.20-mapreduce-jobtracke
+r status | awk '{print $3}'};
print "$status is status of service";
if ( "$status" eq "stopped" )
{
print " JOBTRACKER SERVICE is not running";
}

output
[root@r01mgt ~]# perl testscript.pl
jobtracker is stopped
 is status of service

SHELL COMMAND 
[root@r01mgt ~]# ssh r01mn1 /etc/init.d/hadoop-0.20-mapreduce-jobtrack
+er status | awk '{print $3}'
stopped

[download]

In reply to Assign value of SHELL COMMAND to a variable in PERL by rahulruns

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.