Re: Assign value of SHELL COMMAND to a variable in PERL

I suspect that the problem might be that the system call is resulting in output to STDERR, rather than STDOUT. To redirect, try adding 2>&1 like this:

my $status = qx{ ssh r01mn1 /etc/init.d/hadoop-0.20-mapreduce-jobtrack
+er status 2>&1 | awk '{print $3}'};
[download]

Be sure to put it before the pipe, otherwise you won't be piping anything to awk. Did that help at all?

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Re^2: Assign value of SHELL COMMAND to a variable in PERL by ambrus (Abbot) on Jul 12, 2012 at 07:36 UTC
Good guess, it's definitely worth a try, but it seems the Debian init scripts do write the status output to stdout.	[reply]
Re^2: Assign value of SHELL COMMAND to a variable in PERL by rahulruns (Scribe) on Jul 12, 2012 at 06:56 UTC
The output is same even after change `output [root@r01mgt ~]# perl testscript.pl jobtracker is stopped is status of service` [download]	[reply] [d/l]
Re^3: Assign value of SHELL COMMAND to a variable in PERL by frozenwithjoy (Priest) on Jul 12, 2012 at 07:09 UTC
Out of curiosity, what do you get w/o the pipe to `awk`?	[reply] [d/l]
Re^2: Assign value of SHELL COMMAND to a variable in PERL by jessarah (Initiate) on Jul 12, 2012 at 11:03 UTC
May be this is a more complicated way, but works with me: `my $lcmd="pwd"; open (INPUT,"($lcmd) 2>&1 \|"); @ltext = <INPUT>; close (INPUT); my $result=$ltext[0]; print("Output of pwd: $result");` [download] *Jes	[reply] [d/l]