Exercises

1.	Is each of the following an absolute pathname, a relative pathname, or a simple filename? milk_co correspond/business/milk_co /Users/zach /Users/zach/literature/promo .. letter.0610
2.	List the commands you can use to perform these operations: Make your home directory the working directory Identify the working directory
3.	If your working directory is /Users/zach with a subdirectory named literature, give three sets of commands that you can use to create a subdirectory named classics under literature. Also give several sets of commands you can use to remove the classics directory and its contents.
4.	The df utility displays all mounted filesystems along with information about each. Use the df utility with the h (human-readable) option to answer the following questions. How many filesystems are mounted on your Mac OS X system? Which filesystem stores your home directory? Assuming that your answer to exercise 4a is two or more, attempt to create a hard link to a file on another filesystem. What error message do you get? What happens when you attempt to create a symbolic link to the file instead?
5.	Suppose you have a file that is linked to a file owned by another user. What can you do so that changes to the file are no longer shared?
6.	What are some of the differences between a Finder alias and a hard link or a symbolic link?
7.	If /Users/max/draft and /Users/zach/letter are links to the same file and the following sequence of events occurs, what will be the date in the opening of the letter? Zach gives the command vim letter. Max gives the command vim draft. Max changes the date in the opening of the letter to January 31, 2006, writes the file, and exits from vim. Zach changes the date to February 1, 2006, writes the file, and exits from vim.
8.	Suppose that a user belongs to a group that has all permissions on a file named jobs_list, but the user, as the owner of the file, has no permissions. Describe which operations, if any, the user/owner can perform on jobs_list. Which command can the user/owner give that will grant the user all permissions on the file?
9.	Does the root directory have any files that are hidden in the Finder but displayed by ls? Explain why these files might be hidden.
10.	Assume that you are given the directory structure shown in Figure 4-2 on page 73 and the following directory permissions: d--x--x--- 3 max max 578 Mar 10 15:16 business drwxr-xr-x 2 max max 578 Mar 10 15:16 business/milk_co For each category of permissionsowner, group, and otherwhat happens when you run each of the following commands? Assume that the working directory is the parent of correspond and that the file cheese_co is readable by everyone. cd correspond/business/milk_co ls l correspond/business cat correspond/business/cheese_co
11.	The FAT16 filesystem, also called the MS-DOS filesystem, is inefficient on large disks and imposes stringent filename limits. Why is it important to support this filesystem?
12.	What does the .. entry in a directory point to? What does this entry point to in the root (/) directory?