文件管理

1.The following figure is a file allocation table in main memory, please write out: which disk blocks does file-A use? Which disk blocks does file B use? Which disk blocks does file C use?

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1.下图是主内存中的文件分配表，请写出：文件A使用哪些磁盘快？ 文件B使用哪些磁盘块？ 文件C使用哪些磁盘块？

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Answer：
File A uses disk blocks 4, 7, 2, 10 and 12;
File B uses disk blocks 6, 3, 11 and 14;
File C uses disk blocks 8, 0, 9, 1 and 13
这个就根据图片一步一步找就行了，要注意-1表示结束就可以了

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2.The beginning of a free space bitmap looks like this after the disk partition is first formatted: 1000 0000 0000 0000 (the first block is used by the root directory). The system always searches for free blocks starting at the lowest-numbered blcok, so after writing file A , which uses six blocks, the bitmap looks like this: 1111 1110 0000 0000. Show the bitmap after each of the following additional actions:
(a) File B is written, using five blocks
(b) File A is deleted
(c) File C is written, using eight blocks
(d) File B is deleted

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磁盘分区首次格式化后，可用空间位图的开头如下所示：1000 0000 0000 0000（根目录使用第一个块）。 系统始终搜索从最低编号的blcok开始的空闲块，所以在写入使用六个块的文件A后，位图如下所示：1111 1110 0000 0000.在每个以下其他操作之后显示位图：
（a）文件B写入，使用五个块
（b）文件A被删除
（c）使用八个块写入文件C
（d）文件B被删除

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Solution:
(a)1111 1111 1111 0000
(b)1000 0001 1111 0000
(c)1111 1111 1111 1100
(d) 1111 1110 0000 1100
这题没啥可讲的吧

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3.Consider the directory tree is as follows. If the working directory is \Root\Alice, the relative path name of file ff1 is .\f1\ff1 , and its absolute path name is \Root\Alice\f1\ff1 . And the relative path name of file ff3 is ..\Bob\f3\ff3 , its absolute path name is \Root\Bob\f3\ff3 .

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3.考虑目录树如下。 如果工作目录为\ Root \ Alice，文件ff1的相对路径名为.\ f1 \ ff1，其绝对路径名为\ Root \ Alice \ f1 \ ff1。 而文件ff3的相对路径名为.. \ Bob \ f3 \ ff3，其绝对路径名为\ Root \ Bob \ f3 \ ff3。

一个”.”表示当前目录下，两个”.”表示上一层目录。