Home Frequently Asked Questions UNIX

 

 

 

This page answers common questions related to UNIX.

 

Questions:

 
 
 
 
 


Q: I developed programs, scripts, pages, etc, on a Windows PC. Why won't they work when I move them to a UNIX machine?


A: UNIX is different from PC Operating Systems like Windows.
Java is portable: Operating System environments are not.
If you are experiencing problems with files you moved from a windows machine to a UNIX machine, check the following:


File System differences
Windows machines generally reference files as follows:
c:\java-application\JavaFile.class

UNIX does this differently:
/home/s00-c000-s00/javaserver/WEB-INF/classes/JavaFile.class

Therefore, if you have any code or HTML that depends upon the specific location of other files, be sure to change this code to suit the UNIX environment. There is no c: drive on a UNIX machine!

Suggestion: Use relative addressing whenever possible.


Case Sensitivity
Windows ignores the case of the characters you use in many contexts.
A windows system does not differentiate between:
 
  • DEFAULT.HTM
  • Default.Htm
  • default.htm

UNIX, on the other hand, is case sensitive. UNIX would allow three files named DEFAULT.HTM, Default.Htm, and default.htm to exist in the same directory.

Therefore, confirm that your code or HTML uses case consistently.


Q: Where can I go to learn basic UNIX commands?

 

A: There are many resources available for students requiring a working knowledge of UNIX commands.

 
  • If you want to learn the specifics of a particular UNIX command, type: man command_name
    The man command displays the UNIX manual pages for a particular command. The manual pages are the best sources for learning the subtleties of UNIX commands.
    Example: man ls
    This command will display the manual pages for the ls command.

  • Search the web for UNIX tutorials.
    Search for UNIX tutorials
    You will find many, many websites dedicated to UNIX.
    Find a tutorial that you like and bookmark it.

  • Read books and manuals about UNIX.
    Search for books about UNIX

Q: How can I edit a file in UNIX?

 

A: UNIX offers many options for editing. Here are a few common tools:

 
  • Use the pico editor for simple editing.
    Example: pico myPicoFile.txt
    Note: pico will create a new file called myPicoFile.txt if a file with that name does not already exist.
    pico is a good editor to use if you are a beginner. You will see a list of control keys at the bottom of the screen. Simply use the control keys as needed and type away.

  • Use the vi editor for advanced editing.
    Example: vi myViFile.txt
    Note: vi will create a new file called myViFile.txt if a file with that name does not already exist.
    vi is a good editor to use if you want to become a UNIX poweruser.
    If you decide to use vi, I strongly suggest that you reference online tutorials. Many users find vi frustrating.
    Search for vi tutorials

  • Edit on a remote machine and transfer the files to UNIX.
    If you find the UNIX tools unfriendly, then use any text editor of your choice on the platform of your choice to create and edit files. When you have finished editing your documents, transfer them to the UNIX machine.


Q: How can I connect to a UNIX machine remotely?

 

A: UNIX offers many opportunities for working remotely. You will need to know three things to connect to a UNIX machine.

 
  • The IP address or DNS name of the UNIX machine.
    Example DNS name: vulcan.seidenberg.pac.edu
    Example IP address: 198.105.44.199
  • Your username
  • Your password

 

FTP: File Transfer Protocol
FTP allows users to move files between client machines and servers. There are many graphical FTP clients available for the windows platform. We suggest WS_FTP.


TELNET
TELNET allows users to work on the server interactively. After connecting to the server, a user interacts with the operating system by typing UNIX commands at a prompt.

To initiate a telnet session from a Windows client:
 
  • Open a DOS window
  • Type: telnet ip.address.or.dns.name
  • Supply your username and password when prompted to do so.
 

Secure Shell

Secure Shell combines the capabilities of FTP and TELNET with added security features. We recommend that you use Secure Shell whenever possible. You can download the Secure Shell client software from: http://www.ssh.com/download/


Q: How do I change my password on a UNIX machine?

 

A: Use the passwd command to change your password.

UNIX systems have a fairly high standard for passwords. Be sure to make your password at least 5 characters long. Use a combination of numbers and letters. Use both uppercase and lowercase letters. If the system does not like your password, it will ask you to change your password again. The system gives you three chances to change your password to something it accepts as secure. After the third try, the system will terminate the command. If this happens you must type the passwd command again.


If you have any material (questions or answers) that may be useful here, send them to csis@pace.edu