I have a Perl script that runs from Jenkins slave. The script executes a shell script kept on remote box A. This shell script actually deploys war on machine A itself. Both machines, Jenkins slave and remote box are CentOS instances. 
use strict;
use warnings;
use Cwd;
use File::Copy;
use Getopt::Long;
use File::Basename;
use Net::OpenSSH;

my ($conf_file, $environment, $doexec, $exec, $job, $dest_file, $user,
+ $host, $IP, $TARGET_SERVER, $JENKINS_JOB, $wrapper, $src_file, $src_
+path, $src_dist_path, $src_full_path, $id_file, $ssh, @array, $line);

init();

sub init {
    $JENKINS_JOB = $ENV{'JOB_NAME'};

    $conf_file = "/home/ec2-user/SCM/conf/deploy_build.conf";
    open (FH, "<", $conf_file) or die "Cannot open < $conf_file: $!";

    while (<FH>) {
        if ( $_ =~ /\b$JENKINS_JOB\b/ ) {
            push @array, $_;
        } else {
            next;
        }
    }

    foreach $line (@array) {
        ($job, $src_path, $dest_file, $user, $wrapper) = split(':', $l
+ine);

        $id_file = "/home/ec2-user/.ssh/priv_key";

        $ssh = Net::OpenSSH->new($IP, key_path => $id_file, user => $u
+ser);
        $ssh->error and die "Couldn't establish SSH connection: ". $ss
+h->error;
        
        printf "\n";
        if (length $wrapper) {        
            printf "Initiating subroutine for executing wrapper on rem
+ote machine...\n";
            &exec_wrapper;
        } else {
                printf "*** No wrapper specified ****\n";
        }
    }
}


sub exec_wrapper {
    my ($stdout, $errput) = $ssh->capture2("~/release/$wrapper");

    printf "Output: $stdout\n" if $stdout;
    die "Error: $errput\n" if $errput;
    printf "\n\n\n";
}

[download]
Now the issue is that though the program runs fine, it prints output after a while. Whole output is captured in $stdout and then dumped later. Since this job runs as a Jenkins job, the end user has no idea what's going on until the output is dumped. I wanted to print each line as event occurs (runtime) instead of waiting for the whole output to be stored in the variable and dumped later. I did read this article but i'm not sure whether it applies to my case and if it does, how can i implement it. Just to mention, efficiency is *not* a concern in my scenario. Any help will really be appreciated.

In reply to Print log at runtime instead of dumping all at once later by Technext

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