Friday, August 16, 2019
Is each of the following an absolute pathname, a relative pathname, or a simple filename? a) Mile_co b) Correspond/business/milk_co c) /home/max d) /home/max/literature/promo e) .. f) Letter. 0210 2. List the commands you can use to perform these operations: a. Make your home directory the working directory b. Identify the working directory a. cd; b. pwd 3. If your working directory is /home/alex 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 Ã¢â¬âh (human-readable) option to answer the following questions. $ df -h Filesystem Size Used Avail Use% Mounted on /dev/hda1 1. 4G 242M 1. 1G 18% / /dev/hda3 23M 11M 10M 51% /boot /dev/hda4 1. 5G 1. 2G 222M 85% /home /dev/hda7 564M 17M 518M 4% /tmp dev/hdc1 984M 92M 842M 10% /gc1 /dev/hdc2 16G 13G 1. 9G 87% /gc2 a. How many filesystems are mounted on your Linux system? b. Which filesystem stores your home directory? c. 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? Following are sample answers to these questions. Your answers will be different because your filesystems are different. . six; b. /dev/hda4; c. ln: creating hard link Ã¢â¬Ë/tmp/xxxÃ¢â¬â¢ to Ã¢â¬ËxxxÃ¢â¬â¢: Invalid cross-device link. No problem creating a cross-device symbolic link. 2 Answers to Even-Numbered Exercises 5. Suppose that you have a file that is linked to a file owned by another user. How can you ensure that changes to the file are no longer shared? 6. You should have read permission for the /etc/passwd file. To answer the following questions, use cat or less to display /etc/passwd. Look at the fields of information in /etc/passwd for the users on your system. . Which character is used to separate fields in /etc/passwd? b. How many fields are used to describe each user? c. How many users are on your system? d. How many different login shells are in use on your system? (Hint: Look at the last field. ) e. The second field of /etc/passwd stores user passwords in encoded form. If the password field contains an x, yo ur system uses shadow passwords and stores the encoded passwords elsewhere.