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>dio_truncate</H1
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><P
> (PHP 4 >= 4.2.0, PHP 5 <= 5.0.4)</P
>dio_truncate --
Truncates file descriptor fd to offset bytes
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><DIV
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><H2
>说明</H2
>bool <B
CLASS="methodname"
>dio_truncate</B
> ( resource fd, int offset )<BR
></BR
><P
> <B
CLASS="function"
>dio_truncate()</B
> truncates a file to at most
<CODE
CLASS="parameter"
>offset</CODE
> bytes in size.
</P
><P
> If the file previously was larger than this size, the extra data is
lost. If the file previously was shorter, it is unspecified whether the
file is left unchanged or is extended. In the latter case the extended
part reads as zero bytes.
</P
><DIV
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><B
>注意: </B
>本函数未在 Windows 平台下实现。</P
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><H2
>参数</H2
><P
> <P
></P
><DIV
CLASS="variablelist"
><DL
><DT
><CODE
CLASS="parameter"
>fd</CODE
></DT
><DD
><P
> The file descriptor returned by <A
HREF="function.dio-open.html"
><B
CLASS="function"
>dio_open()</B
></A
>.
</P
></DD
><DT
><CODE
CLASS="parameter"
>offset</CODE
></DT
><DD
><P
> The offset in bytes.
</P
></DD
></DL
></DIV
>
</P
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></A
><H2
>返回值</H2
><P
> 如果成功则返回 <TT
CLASS="constant"
><B
>TRUE</B
></TT
>，失败则返回 <TT
CLASS="constant"
><B
>FALSE</B
></TT
>。
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