'w' indicates that you want to write data to the file, truncating the previous contents.

' w '表示要向文件写入数据，并截断以前的内容。

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The verbose trace will display data from the parameters of system calls (-x all) and the contents of the buffer for both Read (-r all) and Write (-w all) calls.

详细的跟踪会显示来自系统调用参数的数据(- x all)以及Read (- r all)和Write (- w all)调用的缓冲区的内容。

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