擅长:python、mysql、java
<p><a href="https://docs.python.org/2/library/stdtypes.html#file.truncate" rel="nofollow">From the docs:</a></p>
<blockquote>
<p><code>file.truncate([size])</code></p>
<p>Truncate the file’s size. If the optional size argument is present, the file is truncated to (at most) that size. The size defaults to the current position.</p>
</blockquote>
<p>在调用<code>handle.read()</code>之后调用<code>handle.truncate()</code>,此时当前位置是文件的结尾,因此Python会将文件截断为当前大小,但不会执行任何操作。您需要将0作为参数传递给<code>truncate</code>:<code>handle.truncate(0)</code>。在</p>