The first copy (see Figure 1) is performed by the direct memory access (DMA) engine, which reads file contents from the disk and stores them into a kernel address space buffer.

直接内存存取(direct memory access, DMA)引擎执行了第一次拷贝(参见图1)，它从磁盘中读取文件内容，然后将它们存储到一个内核地址空间缓存区中。

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Information allowing direct access to the activity of the company, organisation or person, in particular a domain name or an electronic-mail address, and.

信息可直接进入该活动的公司，组织或人士，尤其是一个域名或电子邮箱地址。

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An address written on a direct access volume, denoting a track's address relative to the beginning of the volume.

记录在直接存取盘卷上的地址，表明相对于盘卷始址的一个磁道地址。

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The SEC has already proposed a number of changes designed to address their growing influence, including extra restrictions on broker-dealers that provide direct market access to high frequency traders, a trader tracking system for large traders, circuit breakers that would slow trading in individual stocks if they fall more than 10%, and new rules for off-exchange trading venues.

FORBES: SEC Wants Real Time Trading Data