Updated: 2000-12-02 15:27

Chapters 6&8 Exercises

Chapter 6     File and Directory Permissions

(Pages 375-398) 

6-1.     File permissions are set for three classes of users. Name these three classes.

6-2.     Give the command used to set the read permissions for a file called myfile. Give the command to unset the read permissions for the file.

6-3.     Which command and option is used to find out the permission settings for files and directories?

6-4.     What does a letter d in the first character of the permissions field signify?

6-5.     If a directory has 4 in its link field, name the four possible links.

6-6.     Can you change the permissions of files that belong to other accounts, if they give you full permission to write the files?

6-7.     If a file of yours has rwxr-xr-- in its 9-character permissions field, what permissions do group members have on this file?

6-8.     After you issue "chmod 421" info, explain in words what permissions the group members have on this file.

6-9.     Give the resulting permissions (9 characters long) after issuing the commands:
              chmod  751  info1
              chmod  641  info1
              chmod  450  info1
              chmod  321  info1
              chmod  000  info1

6-10.     Create the info file with vi as indicated on page 381. Change its permissions to 700 and test the four commands given in step #2 on page 394. Test it again with permissions 600, 500, ..... Complete Table 6-2 on page 395.

6-11.     Do the questions of Review 1 on page 298.  The rest of this chapter is optional reading.

Chapter 8     Processes

(Pages 458-474)

8-1.     Which of these actually creates a new process?
              a. when a command is being interpreted by the Shell.
              b. when a utility is being executed.
              c. when a job is placed in the background.

8-2.     Name the term that describes the creation of a process. Name the term describing the ending of a process.

8-3.     Describe the typical computer activities generated by a process.

8-4.     Explain why a process usually needs to be connected to a port or a tty.  (Some system processes aren't connected to any terminals.)

8-5.     What does the shell do after it instructs the kernel to execute a command that it has found?

8-6.     How does the kernel actually start a process when given a command name by the shell?

8-7.     When a process terminates, what piece of information is brought back to the waiting shell?

8-8.     State the command that will generate a long (verbose) listing of your processes.

8-9.     How do you check out the exit status of the command that just completed?

8-10.     Answer the questions asked in Review 1 on page 470.

8-11.     What is the default signal name and number used when you issue a kill process command with no arguments?

8-12.     What is the signal name and number sent when you type CTRL-C?

8-13.     Explain how you can use the echo command to display the process ID of the shell you are in.

8-14.     Which signal name and number is guaranteed to kill a process that you own?

8-15.     Explain how to display a list of the available signals sent out by the kill command.

8-16.     If you issue "sh ; who", what are the parent processes for sh and who?  (Hint: When will you see the output of who?)

8-17.     Answer the questions of Review 2 on page 474.

Web Author: Ian! D. Allen idallen@ncf.ca
Updated: 2000-12-02 15:27