I assume you mean if (!$?) and not if (!?). Anyway.

From perldoc perlvar: 

       $?      The status returned by the last pipe close,
               backtick (``) command, or system() operator.  Note
               that this is the status word returned by the
               wait() system call (or else is made up to look
               like it).  Thus, the exit value of the subprocess
               is actually ($? >> 8), and $? & 127 gives which
               signal, if any, the process died from, and $? &
               128 reports whether there was a core dump.
               (Mnemonic: similar to sh and ksh.)

[download]

In other words, your process terminates with an exit status of zero (which should be correct), dying from signal 13, which happens to be SIGPIPE.

Enough hints? :-)

-- TMTOWTDI

In reply to Re: calling an external program, from within a perl script by trantor
in thread calling an external program, from within a perl script by nick

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