system does not capture the command's output, for that I would recommend capture or rather capturex from IPC::System::Simple. Perl does have this functionality built in, but I usually recommend staying away from it, for reasons I explained here (along with other modules and sample code). In addition, you should validate that $in and $out look as you expect before feeding them into rrdtool. Since AFAICT they should normally be numbers, I'm using Regexp::Common to validate them.

use warnings;
use strict;
use IPC::System::Simple qw/systemx capturex/;
use Regexp::Common qw/number/;

while (1) {
    my $in  = capturex(qw/ snmpget -Oqv -v2c -c randomstr localhost 1.
+3.6.1.2.1.31.1.1.1.7.3  /);
    my $out = capturex(qw/ snmpget -Oqv -v2c -c randomstr localhost 1.
+3.6.1.2.1.31.1.1.1.11.3 /);
    for ($in,$out) {
        chomp;
        die "Bad number '$_'" unless /^$RE{num}{real}$/;
    }
    systemx('rrdtool','update','opit11.rrd',"N:$in:$out");
    sleep 10;
}

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In reply to Re: Update RRD by haukex
in thread Update RRD by bachoA4o

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