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copied!<p>On most Unix platforms, the <code>CHLD</code> (sometimes also known as <code>CLD</code>) signal has special behavior with respect to a value of <code>'IGNORE'</code>. Setting <code>$SIG{CHLD}</code> to <code>'IGNORE'</code> on such a platform has the effect of not creating zombie processes when the parent process fails to <code>wait()</code> on its child processes (i.e. child processes are automatically reaped). Calling <code>wait()</code> with <code>$SIG{CHLD}</code> set to <code>'IGNORE'</code> usually returns <code>-1</code> on such platforms.<br> <em>Excerpted from <a href="http://perl.active-venture.com/pod/perlipc-signal.html" rel="nofollow">http://perl.active-venture.com/pod/perlipc-signal.html</a></em></p> <p>Basically what is happening is that somewhere the <code>CHLD</code> signal has been set to <code>IGNORE</code> <em>probably by sqlldr</em>. When you attempt to check on the status of the child process you receive the <code>-1</code> which is sometimes referred to as <code>ECHILD</code>. This occurs because the information about the completion status of the child process has been discarded due to the ignoring of the <code>CHLD</code> signal. By setting <code>$SIG{CHLD} = 'DEFAULT';</code> you are indicating that the CHLD signal should be handled by the DEFAULT handler and not ignored.</p> <p>I do not know why the <code>CHLD</code> signal is being ignored when the script is executed from sudo user versus being executed directly from your user id.</p>

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