check perlvar and you will get this 

$CHILD_ERROR
    $?      The status returned by the last pipe close, backtick (``)
            command, successful call to "wait()" or "waitpid()", or fr
+om the
            "system()" operator. This is just the 16-bit status word
            returned by the traditional Unix "wait()" system call (or 
+else
            is made up to look like it). Thus, the exit value of the
            subprocess is really ("$? >> 8"), and "$? & 127" gives whi
+ch
            signal, if any, the process died from, and "$? & 128" repo
+rts
            whether there was a core dump.

[download]

update:

sorry, misunderstanding the question

you have got the return value of the backtick command. just as CountZero posted.

In reply to Re: get return value from jar file by vinian
in thread get return value from jar file by Anonymous Monk

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