To simplify detecting success or failure, I just echoed success or failure. I also made some other corrections to your attempt:

• Used && instead of ; so that tar extraction is not attempted if the cd fails.
• Changed the parens to create sub-shell on RHS.
• Used . rather than * in the tar command to get all files in the dir (even those starting with .) and to ensure all sub-dirs are (recursively) copied.
• Removed verbosity on tar command.

$ pwd
/home/knob
$ cat t1.sh
#!/bin/ksh
if tar cf - . | (cd /var/tmp/dump && tar xf -); then
   echo "success"
else
   echo "failure"
fi
$ rm -fr /var/tmp/dump
$ ./t1.sh
./t1.sh[2]: /var/tmp/dump:  not found.
failure
$ mkdir /var/tmp/dump
$ ./t1.sh
success
$ ls -l
total 8
-rwxrwxrwx    1 knob    devel         108 30 Aug 17:51 t1.sh
$ ls -l /var/tmp/dump
total 8
-rwxrwxr-x    1 knob    devel         108 30 Aug 17:51 t1.sh
[download]

Note that, for simplicity, I created a scratch directory (/home/knob above) containing just the test script itself t1.sh and cd'ed into this directory -- so this is the directory that is copied. If yours does not work, post the output of running your command (as I did above).

Update: If all you want to do is to make a recursive copy of a directory, File::Copy::Recursive is a good alternative.

this isn't really a Perl question, but my quick tests (though not exactly your syntax) return a non negative value, usually 2, when tar fails.

Did you try to run the shell command from the shell prompt (i.e. not from your Perl script)?

A TMTOWTDI not using ksh (considered harmful) - not thoroughly tested and written in a hurry (but also assuming that using tar is the most performant way for recursive copying of dirs):

#!/usr/bin/env perl    

use strict;
use warnings;
use Capture::Tiny qw(capture);
use Path::Tiny;
use feature qw (say);

my $source = qq(nose/);
path("failure.ok")->touch && die $! unless -e $source;

my $target = qq(fubar/);
path("failure.ok")->touch && die $! unless -e $target;

my $tar = qq(tar cf - $source | (cd $target && tar xvf - ));

my ( $stdout, $stderr, $exit ) = capture {
    system($tar);
};

say $stdout;
say $stderr;
say $exit;

$exit ? path("failure.ok")->touch : path("success.ok")->touch;

__END__
[download]

IPC::Run might also be interesting.

Best regards, Karl