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>pcntl_fork</H1
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><P
> (PHP 4 >= 4.1.0, PHP 5)</P
>pcntl_fork -- Forks the currently running process</DIV
><DIV
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><H2
>说明</H2
>int <B
CLASS="methodname"
>pcntl_fork</B
> ( void )<BR
></BR
><P
> The <B
CLASS="function"
>pcntl_fork()</B
> function creates a child
process that differs from the parent process only in its PID and
PPID. Please see your system's fork(2) man page for specific details as to
how fork works on your system.
</P
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><H2
>返回值</H2
><P
> On success, the PID of the child process is returned in the
parent's thread of execution, and a 0 is returned in the child's
thread of execution. On failure, a -1 will be returned in the
parent's context, no child process will be created, and a PHP
error is raised.
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>范例</H2
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><B
>例 1. <B
CLASS="function"
>pcntl_fork()</B
> example</B
></P
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><code><font color="#000000">
<font color="#0000BB"><?php<br /><br />$pid </font><font color="#007700">= </font><font color="#0000BB">pcntl_fork</font><font color="#007700">();<br />if (</font><font color="#0000BB">$pid </font><font color="#007700">== -</font><font color="#0000BB">1</font><font color="#007700">) {<br /> die(</font><font color="#DD0000">'could not fork'</font><font color="#007700">);<br />} else if (</font><font color="#0000BB">$pid</font><font color="#007700">) {<br /> </font><font color="#FF8000">// we are the parent<br /> </font><font color="#0000BB">pcntl_wait</font><font color="#007700">(</font><font color="#0000BB">$status</font><font color="#007700">); </font><font color="#FF8000">//Protect against Zombie children<br /></font><font color="#007700">} else {<br /> </font><font color="#FF8000">// we are the child<br /></font><font color="#007700">}<br /><br /></font><font color="#0000BB">?></font>
</font>
</code></TD
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</P
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><H2
>参见</H2
><P
> <P
></P
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><A
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><B
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>pcntl_waitpid()</B
></A
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><A
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><B
CLASS="function"
>pcntl_signal()</B
></A
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