在《linux设备驱动程序》一书中，scull（simple character utility for loading localities,"区域装载的简单字符工具"）
是一个操作内存区域的字符设备驱动程序，这片内存区域就相当于一个字符设备。
scull的优点在于他不和任何硬件相关，而只是操作从内核分配的一些内存。任何人都可以编译和运行scull,而且还看看可以将scull移植到linux支持的所有计算机平台上。但另一方面，除了展示内核和字符设备驱动程序之间的接口并且让用户运行某些测试例程外，scull设备做不了任何“有用”的事情。
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002988s ]
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UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 276966 [ RunTime:0.001416s ]
