Jason Martin
CS126-1501A-02 Unix Fundamentals
01/12/2015

UNIX Commands – Input and Output
1.) The cd or “change directory” command will show you where you are currently at within the directory structure. The command is intended to allow a user to move throughout the shell’s directory structure to add, delete, or to make any necessary changes to a file system. In this example, since the cd command was only used without any path, then it will keep a user in the current directory.
2.)
The mkdir or “make directory” command allows the user to create a directory within the directory structure or file system. In the above command the intention was to create a directory named apache in the file system. As you can see with the ls command, apache is now a directory within the home or root directory.
3.)
The cd APACHE command is intended for the user to access or choose the APACHE directory. However, UNIX is case sensitive and sense the directory is lowercase (apache), you receive a no such file or directory.
4.)
The cd apache command is similar to the previous command, however, when this specific command is entered in the shell, it moves the user into the apache directory within the file system. You can determine which directory you are in by seeing ~/apache#. This shows that you are in the apache directory within the root or home directory.
5.)
The pwd command shows the user the path to the current directory that they are working in. In the screenshot above, you can see that I’m in the apache directory and by using the pwd command I can see the specific path to the apache directory. The path is /root/apache. So I’m in the apache directory within the root or home directory. 6.)
The command cd ../../../../../../../etc sends the user to the /etc directory as this can be verified with the ls command which shows all the files such as configuration files in the etc file. The ../ signifies going back a directory in the file system, so in this particular case we are going back in the structure numerous times. No matter how many times you use the command to go back a directory, when the etc command is added it will direct you to the /etc directory.
7.)
The cd /etc command’s output is identical to the previous command cd ../../../../../../../etc. Both commands will send you to the etc file directory which can be confirmed by the files in the etc directory. You can refer back to question 5 and notice the same files to ensure that it is the same etc file within the directory structure.
8.)
The cat passwd command in this instance will display the contents of the etc password file within the file system. You can see the etc password file in the above screenshot. The cat command is a display command so we want to display or show the password file and since we are in the /etc directory it will show the /etc password list.
9.
The more passwd command is a convenient way to see more of a specific file which is too large to view in the shell. In the above example with the password file of etc. If you want to see if there is more to a file such as a text file you can use this command. As you can see at the bottom there is more highlighted in white and the percentage of what you have seen of the file so far. By pressing enter, this will increase, allowing the user to view more of the file line by line.