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1.What does it mean to have execution permission on a directory? 2.What is the c

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Question

1.What does it mean to have execution permission on a directory?

2.What is the chmod command for changing the file a.out’s permissions so that the owner can read, write, and execute; the file’s group can read and execute; and everyone else can only execute.

3. Assuming the block size is 4096 bytes and physical disk block addresses are 32 bits, how many blocks can we address using the triple indirection pointer in the UFS pointer structure?

4. Consider a file system similar to the one used by UNIX with indexed allocation. How many disk I/O operations might be required to read the contents of a small local file, which fits within one block, at the directory /users/jae125/cs410/? Assume that none of the disk blocks is currently being cached.

5. What is the advantage of using a file-allocation table (FAT) to chain together the blocks of a file in linked allocation?

Explanation / Answer

1.

While applying permissions to indexes on Linux the authorization bits have unexpected implications in comparison to on customary documents.

The write bit enables the influenced client to make rename or erase documents inside the registry and change the index's characteristics

The read bit enables the influenced client to list the records inside the catalog

The execute bit enables the influenced client to enter the registry and get to documents and indexes inside

The sticky piece expresses that documents and indexes inside that catalog may just be erased or renamed by their proprietor (or root)

2.

400 Read by owner

200 Write by owner

100 Execute by owner

040 Read by group

020 Write by group

010 Execute by group

004 Read by others

002 Write by others

001 Execute by others

To make a get to mode whole every one of the gets to you wish to permit.For case to give read privileges to all and compose and execute benefits to the proprietor just for a document you would total: 400+200+100+040+004 = 744. At that point at the Unix prompt you would enter:

chmod 744 myfile.ext

Some other frequently used examples are:

777 anyone can do anything (read, write, or execute)

755 you can do anything; others can only read and execute

711 you can do anything; others can only execute

644 you can read and write; others can only read