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Table of Contents
What is this Document About?
This document gives you the basic information you need to use your
TerpConnect (formerly Glue) or GRACE Unix account. It provides the basics
for managing files in Unix, the operating system of the computer where your
TerpConnect or GRACE account resides.
This document assumes that you are using your TerpConnect or GRACE account
from a terminal window by using a computer in a lab, an office at
the University, or at home.
Note: Access to OIT Computer Labs at the University is limited. You
must have a valid University ID to use the labs.
Information on connecting to a TerpConnect or GRACE host computer from an
OIT Computer Lab is available in other Office of Information Technology (OIT)
documents, including:
For information regarding University residence hall network connectivity,
see
How To Set Up Your Computer On The Dorm
Ethernet or call 301.314.DATA.
All TerpConnect and GRACE accounts are governed by the
University of Maryland Guidelines
for the Acceptable Use of Computing Resources.
Conventions Used in this Document
This document uses several fonts to help clarify the meaning of the
text:
| light text |
This courier text is for characters and text displayed on your
screen by the host computer. |
| bold text |
This courier text is for words or characters you type. |
| italic text |
Places an emphasis on terms. Also used as a general word or phrase
for which you must substitute a specific example (for
your-loginname you substitute johndoe). |
When referring to pressing the Enter or Return key on the
keyboard, we'll say "press Enter".
Note: Unix is case-sensitive. This means it makes a difference
whether you type commands or filenames in UPPER or lower case. Thus
FILE3 is different from file3.
How Do I get a TerpConnect Account?
To apply for a new TerpConnect account, go to
http://www.oit.umd.edu/new/.
You will see the OIT Welcome page, select the category pertaining to your
status at the university. Follow the instructions on the application. Complete
details on the application process are presented when you login.
TerpConnect accounts are only for University of Maryland College Park
students, faculty and staff.
How Do I Get a GRACE Account?
The GRACE (Glue Research and Academic Computing Environment) cluster
has been established for instructional and research usage of the faculty,
staff and students of the University of Maryland College Park. It is a
cluster of four Unix servers, two running Solaris and two running
RedHat Enterprise Linux, and is part of the TerpConnect system.
To access the GRACE cluster you must first have a TerpConnect account.
Request a TerpConnect account here.
Instructors who wish to use the GRACE cluster for their class can request
access
by filling out this
form. Researchers who wish to use the GRACE cluster for their
projects can request access
by filling out
this form.
There are general information pages on the system
available at http://www.grace.umd.edu. Here
is a
general overview of the GRACE cluster written by a professor in the
Computer Science department.
Connecting to Your TerpConnect or GRACE Account
To establish remote access to your TerpConnect or GRACE account, you must
make a terminal connection.
One way to make a terminal connection and access your account
is to use a terminal program. Terminals allow you to access the TerpConnect
and GRACE servers. Below are the basic steps to getting started with terminal
programs.
Connecting with Terminal Applications on Windows PCs and Macs
It is generally more secure to connect to your TerpConnect or GRACE
account with a terminal application that uses SSH (secure
shell). Terminal applications that use SSH include:
- F-Secure(text-only for Windows PCs)
- XLiveCD (X Windows display manager for Windows PCs)
- Terminal (text-only for Mac OS X; this is a default application
in Mac OS X)
- Mac X11 (X Windows display manager for Mac OS X)
To obtain one of the programs above, see
http://www.helpdesk.umd.edu/topics/applications/terminal/.
Logging in for the First Time
Once you've established a connection with the TerpConnect or GRACE system,
you may see a prompt on the screen:
login:
Type your login name and press Enter. Your login is your
UM Directory ID.
Then you will see a prompt:
Password:
Type your password (it will not be displayed when you type it) and press
Enter. Remember that Unix is case-sensitive, so you must type your
password exactly as you typed it when you selected it. You will then be
logged in. In some environments you may see a prompt:
TERM = (unknown)
If you do, type vt100 and press Enter (unless you
think your workstation is set up for a different terminal type, in which case
you should use that type).
Next, you will see a prompt that will give the name of the machine you
are logged in to, followed by :~:.
Some typical prompts include:
y:~:
z:~:
baby:~:
scary:~:
When we refer to a command prompt throughout this document, we are
referring to the prompts illustrated above.
Logging Off
To log off (or exit) from your TerpConnect or GRACE account, type
logout at the command prompt and press Enter.
It is important to log off when you finish using the TerpConnect or GRACE
system so that no one else uses your account.
You are liable at all times for the activity on your account - including
e-mail and posting of news articles. All TerpConnect and GRACE accounts are
governed by the
University of Maryland
Guidelines for the Acceptable Use of Computing Resources.
Ending Your Linux Workstation Session: Logout Procedures
If you use a Linux workstation to access your TerpConnect or GRACE account,
you must logoff when you finish your work.
When you have completed your work on the workstation, logout of your
account by selecting Logout from the Dash menu. When you select
the Logout option, you will be asked: Do you really want to
logout? Your choices are: Yes, really logout or No,
continue this session.
Another way to terminate your session on the workstation is to click
and hold down the mouse button while the mouse pointer is positioned on the
desktop. This will display the Utilities menu and from this menu you
can select the Logout option. You will be given two choices in case
you have decide at this point that you do not want to logout:
Really Logout? or No, Don't Logout.
A final way to logout is to type logout or
exit at the Unix prompt.
Changing Your Password
It is important to change your password on a regular basis, and any time
you suspect someone else may know it. To change your password, type:
passwd
at the command prompt. You will be asked for your old password once and
your new password twice; nothing will appear on the screen as you type. Your
password should be difficult for others (or computer programs) to guess. Do
not use a word or name in any common language, spelled either forward or
backwards. Your password must contain at least eight (8) characters and
include both numbers and letters.
Another way to change your TerpConnect or GRACE password is to
change your UM Directory
password.
Note: Remember that UPPER and lower case are not the same in Unix.
Using the Linux Workstation
Linux workstation computers in the OIT Computer Labs fulfill the role of
integrated Unix workstations providing high-power computing and graphics at
individual workstations at the University.
Getting Started on the Linux Workstation
The Linux workstations use the X Windows interface. X Windows
is a graphical user interface which allows users to interact with icons,
buttons, menus and windows, using a pointing device like a mouse. While
similar to other window-based interfaces (e.g., Windows XP and
Apple OS X), X Windows behaves differently.
The Linux workstation mouse behaves as a Windows PC workstation with two
buttons. If you are asked to click (quickly press the mouse button
and release), double-click (click twice in rapid succession), or press
a mouse button without being told which one, use the left mouse button.
For more information on maneuvering windows and icons, refer to
Manipulating Windows and Icons.
Moving the mouse causes the cursor (a symbol on the screen) to
move. The cursor may look like an "X" (when moving between windows), a
vertical bar (when entering text), a pointing hand (when selecting items
from a menu), or it can also appear in some other form depending upon the
software being used.
When you approach a Linux workstation, you should see a window similar to
the illustration below:
Enter your TerpConnect login-name (Directory ID), press the
Enter key and enter your password in the appropriate box
and press the Enter key again to begin your
session. If you make a mistake and you want to correct your
typing, press the Back Space key to remove the text you typed.
If your login-name/password combination is incorrect, try again. Make sure
that the case (i.e., upper or lowercase) of your login-name
and password are correct. If you still have trouble, visit the
OIT Help Desk.
As your login-name and password are processed, a preliminary window is
displayed, similar to the illustration below. This display will indicate the
time of your last login, and if you click on /etc/motd, you can view
any important messages of the day.
Click on the area of the display labeled "Click here to continue"
or wait momentarily for the workstation to continue processing.
After a few seconds, your display screen will look similar to the
illustration below.
Fundamentally, X Windows includes the root window, the mouse
pointer and the window manager.
The upper left and lower right windows (Xterm windows) are
available for you to enter Unix commands. All other windows (including
Xterm windows) and the pointer are "drawn" above the background root
window. The root window is analogous to the desktop on a Macintosh. More
information on the desktop will be discussed later.
When you move your mouse pointer within either of the two
windows, the window is activated. You will notice that the shade intensity
of the window changes when you move the mouse pointer within the window.
You don't have to click the mouse button to switch between windows!
The lower left window is the console window. This is where system messages
are posted.
OIT Computer Lab Linux workstations use the FVWM2 window manager.
It is the default (preset) window manager. A window manager is a special
program which controls the location and behavior of X windows elements.
The look and feel of X windows is completely determined by the
configuration of a window manager and this document focuses upon the
capabilities of the workstations from the context of FVWM2.
The Button Bar
The lower right window is the Button Bar. The Button Bar
includes a collection of application icons (pictures representing
applications). See the Applications section of this
document for more information on application programs.
The root window (or desktop) is analogous to having
various objects on a desk surface that can be moved to various positions
on the desk. The left, center, and right mouse buttons can each be used on
the desktop to display selections and features.
Using the Main and Misc Virtual Desktops
Unlike most PC and Macintosh systems, the desktop is not limited to the
size of your screen. The desktop on the workstations has extended
space, known as the virtual desktop, that is greater than the physical
size of your screen. The virtual desktop feature is similar to having a very
large screen in which you can only see portions of the screen at a time.
Linux workstations in the OIT Computer Labs have two virtual desktops,
each with a size set four times the size of your screen. These desktops are
Main and Misc. You can switch between them by clicking on the
one you want from the Button Bar.
When you take a close look at Main and Misc, you can see that each one is
divided into four quadrants - making four areas of the desktop available
for viewing purposes. If you click on one of these quadrants, your screen
display will switch to the selected area of the virtual desktop. If you
examine each quadrant even closer, you will notice that small boxes have
been used to represent the placement of your windows on the virtual
desktop. You can drag any one of these windows to another area of the
virtual desktop.
WinList
If you click and hold down the right mouse button when the mouse is
positioned on the desktop, you will see a listing of windows (WinList)
that you have opened. When you select any application listed
on the WinList, you will automatically be switched to the window
where that application resides.
Sticky Windows
A sticky window is a window that stays in view all the time, even
when you move around on the virtual desktop. The default (preset) settings
on your TerpConnect account establish two sticky windows: xconsole and
Button Bar. So when you click on any quadrant of Main
and Misc, xconsole and Button Bar will follow you around.
To change a window's sticky properties, select (Un)stick
from the WinOps menu. For more information on the WinOps
menu, refer to the section on Manipulating Windows and
Icons in this document.
The Dash Menu
The Dash menu runs across the top of your display screen.
Dash is an application that gives you easy access to other applications.
When you click on any item on the menu bar, a drop-down menu will appear.
There are several types of items that can appear on a drop-down menu as
illustrated below.
Note: If the Dash bar at the top of the screen does not appear,
type 'dash-show' which should re-start the Dash menus.
If an item is dimmed on the menu, this indicates that it is not on the
current workstation, but is available on other systems.
When you click on a directional arrow to the right of a menu item, a
submenu is displayed with additional choices.
A menu item that has a question mark (?) to the right of the menu
item indicates that additional information relating to the item will
appear.
Many of the items will have both a question mark and an asterisk
(*) associated with the item. For these items, helpful information will
appear to describe the item and indicate how to run the application
program associated with the item. For example, in the above illustration
Utilities has been selected from the Dash menu, followed by the
selection of Backgrounds, and then Background Colors. Following
Background Colors, the colors are listed.
Applications
Applications are programs available on the Linux workstations. When
you select Applications from the Dash menu, it will include a listing of
accessible programs. Included in this listing is Tap.
Tap initializes your entry into an application. To display a listing of
various applications, move the mouse pointer to the Dash menu, select
Applications and then click the right arrow next to any of the
alphabetized groups of applications. For example, to find the Word
Perfect application, click on the right arrow next to the alphabetized
category for Word Perfect.
When you tap an application, you may receive a preliminary display
before your actual entry into the application. You may be required to type a
command or click on an OK button before you successfully enter the
application.
Descriptions of some of these applications are given below,
including some of the more useful applications located on the Button
Bar, including: Xdir, Mail, Music, Xterm, and Xlock.
Island - This is an office suite of tools, including Island Write
(document processing), Island Draw (graphics), Island Chart (graphing charts
and tables) and others.
Mail - The e-mail program on the Button Bar uses the pine
utility for sending and receiving standard e-mail to and from any other
computers on the Internet or other attached networks. Standard Unix mail
programs (as well as pine) can be used from within a Unix terminal window and
from other programs that have a built-in mailer.
Music - This is a feature that gives you the capability of
listening to music from a compact disk (CD).
You must have headphones for listening.
Xdir - A tool that provides assistance in file management. It is a
graphical display of the structure of files and directories on your
account.
Xlock - Locks your workstation for a period of time until you are
ready to use it again. This eliminates the need to logout and login when you
leave your workstation momentarily. Do not leave your workstation
locked for more than five minutes, it will allow others to logout your
session.
Xterm - A Unix terminal window. Xterm allows you to open standard
ASCII terminal windows for Unix commands.
Star Office - A productivity suite similar to MS Office with
which it can share files.
WordPerfect 8 - A word-processing program. OIT Computer
Labs also have Unix text editor utilities which can be used from a
terminal window. These include: Vi, Emacs, and Pico.
There are also a number of programming languages available in the Unix
environment: C, C++, Perl and Java.
A C compiler is available through the cc command. Another, though
quite different, object-oriented extension to the C programming language is
C++. The C compiler is also a C++ compiler.
Manipulating Windows and Icons
The mouse can be used to move windows around, change window sizes, close
windows, and iconize (miniaturize) windows. An example of a typical Xterm
window is shown below. A border encloses each window.
You can move a window by dragging the title bar or most of the frame,
with the exception of the corners. To drag the title bar, move the mouse
to the bar at the top of the window, press and hold the left mouse button,
then move the window to a chosen position and release the mouse button. You
can also move the window by dragging the side bar located on all four
sides of the window.
When you double click the left mouse button on the title bar, the
active (highlighted) window will move to the back. Using the center
button on the title bar will toggle the window from the "foreground" to the
"background", and the right button will pop up the Window Ops
menu. There are several other buttons located on the title bar.
When you click on the Testudo (turtle) button, a drop-down Window
Operations menu will appear with choices available for you to Restore,
Move, Size, Minimize Maximize and Close a window. When
you choose Close from this menu you are initiating your exit from the
application you are working within.
You can iconify a window (i.e., convert it into an icon) by clicking on
the hyphen button on the right side of the title bar. Icons can be
moved by dragging any part of the icon. To return to a full-size window,
double click on the icon.
When you click on the maximize button, 80% of the screen height is in
view, and when you click and hold down the maximize button, 100% of the
screen height is displayed. A double-click on the maximize button will
toggle you between the original size and the whole screen.
With the X button you can close a window but not logout. Always logout
of your account before leaving the workstation.
Note: Refer to Ending Your Linux Workstation
Session: Logout Procedures for more information.
Dragging any frame (corner) of the window will allow you to change
the dimensions of the window. Clicking the left mouse button
anywhere on the frame will begin a resize operation. Clicking the right
mouse button anywhere on the frame will drop down a list of functions
that you can perform on a window (i.e., Window Operations). If you decide you
don't want to perform a window operation, click anywhere on the root
window (desktop) to dismiss this menu.
By using the scroll bar located on the left side of the window, you
can move parts of a window into view. Use the left button on
the scroll bar to scroll down and the right button to scroll up. A
single click on the center button on the scroll bar will move your
current view of the window to the position you clicked on. You can also click
and hold down the center button to scroll the screen to the desired position.
Moving your current view of the window can be confusing for new users who are
already at the bottom of the screen and click the left mouse button to
move down. No scrolling will occur and the current position indicator will not
move.
Using Floppies and CDs
The Linux workstations can accommodate standard 3.5 floppy disk and CDs.
Using floppy disk provides an alternative means of accessing a Unix file.
Linux workstations can read and write Unix formatted disks as well as DOS
formatted disks.
Floppies formatted on Linux workstations can only be used on those
workstations. Floppies formatted as DOS disks also be used on PC's and
Macintoshes. It is not currently possible to read or write Macintosh
formatted disks on the Linux workstations. To format a floppy disk for
Unix, at the Unix prompt type:
fdformat
When you are ready to use a floppy disk, you must mount the floppy
disk. To mount a floppy disk, insert the disk in the drive, move your mouse to
a Xterm window and type:
volcheck
It is important to note that when you mount a floppy disk, the disk drive
is established as a separate file system with files and directories branching
from the /floppy directory.
To eject a disk from the Linux workstation, move to an Xterm window and
type:
eject floppy
Your current working directory cannot be on the floppy disk when you eject,
otherwise you will get an error.
Note: There is no auto eject upon logout, you must eject your floppy
disk before you logout.
Files can be copied between the Linux workstation and the floppy disk by
using Xdir to drag the icons for the files onto the icon for the floppy
disk.
When using this method to copy files, be sure that the tunneling icon is
in the off position. The tunneling icon can be toggled on and off by
clicking once on the icon. The on position can be observed when the
icon appears to be filled.
Copying can also be performed using standard Unix commands (for example,
cp and tar) from a Unix terminal window.
The CD drive is located on the front of the Linux workstations. A button
on the drive will eject a tray where CDs are inserted. The tray
is made of plastic, do not to press down on the tray or lean on it
when inserting the CD. This will damage the tray.
If you wish to use the CD player to listen to a music CD, after inserting
your CD, click on the Music button on the Button Bar. This interface
acts as a CD player with play, pause, stop and change track buttons.
Sound cards are not available in OIT Computer Labs, but you can listen
to audio CDs if you attach a set of headphones to the jack on the front of
the CD drive.
Note: If you are experiencing any problems acknowledging the use of
a floppy disk or CD, call the OIT Help Desk.
Help and Information
The underlying operating system on the Linux workstations is a hybrid of
Berkeley Unix and System V Unix. While some of the operating system-level
functions are Linux-specific, standard Unix documentation will be helpful in
many situations. Unix documentation can be accessed on-line by using the Unix
man command from a terminal window (i.e.,
man man ). General computing help is available from
the OIT Help Desk.
E-mail
Your e-mail address is your login name with @umd.edu attached to
the end. So, if your login name is jdoe, your e-mail address is:
jdoe@umd.edu
This is the address you should give when you are asked for
your e-mail address.
Note: Your TerpConnect account
cannot receive e-mail; all mail is automatically forwarded to your Mail@umd
account. The only exception to this is if your academic
department/unit runs it's own mail server; contact your local departmental
tech support to inquire about this potential feature.
For more information about Mail@UMD, see
https://www.oit.umd.edu/email.
Sending and receiving e-mail on the TerpConnect system can be done using
a number of different tools. We have selected Pine as the tool to
discuss in this document because it can be used from any kind of computer.
In addition, it has many advanced features.
For information about using graphical interface e-mail clients such as
Thunderbird, Outlook, Outlook Express or SeaMonkey to read your e-mail, see
http://www.helpdesk.umd.edu/topics/email/os/windows or
http://www.helpdesk.umd.edu/topics/email/os/mac .
Starting the Pine Mail Program
To start Pine, type pine at the command prompt and press
Enter. You will see Pine's Main Menu screen. On this screen
you will find the options you will normally use to read and send mail. You
can return to the Main Menu at any time during your mail session by
typing m. The Main Menu options enable you to enter
various Pine environments. To select an item from the Main Menu, you
can either type the letter associated with the command name (c
for Compose Message), or you can use the up/down arrow keys to highlight
a selection from the menu and then press Enter.
Note: To use the Pine program to read e-mail on the Mail@umd system
you'll need to modify it's configuration to read & write to/from the
remote system instead of the local system. To do this, you simply need to
run the command:
migrate-pine
from the Unix prompt ONCE, after which it will access your INBOX and other
folders from the Mail@umd system. If you had previously used e-mail on the
TerpConnect system, you will still see your old mail folders as a separate
collection.
- Compose Message allows you to write mail messages to other
people.
- Folder Index gives you a list of the mail items in your current
folder (which is usually your incoming mail or Inbox).
- Folder List allows you to view a list of
items from the Local listing. After you highlight
Select Here to See Expanded List from the Local
section, press the Enter key to view the
items.
- Address Book allows you to set up nicknames
for people (or groups of people) so you don't have to
remember e-mail addresses.
Many Pine commands can be selected by typing a single letter (without
pressing Enter). There are additional commands available at the bottom
of the screen - the collection varies from screen to screen (e.g., the commands
you use when composing mail differ from those you use when working on your
address book). Type o (Other Commands) to view a
list of additional commands. Using Other Commands will change the list
to a new set of commands. Sometimes there are three sets of such commands.
To receive general information on using Pine, type ?
(Help) from the Main Menu. This will give you information on
all Pine commands.
Note: If you have a Mail@UMD account, you can use Pine to read
your e-mail. For more information about setting up Pine for Mail@UMD, see
http://www.oit.umd.edu/mailatumd/whichserver.cgi.
Reading Mail
To read mail that has been sent to you, choose Folder Index from the
Main Menu (highlight the Folder Index selection and press
Enter, or type i). If you have messages in your INBOX,
you will see a list of your mail.
If you have expanded your folder collection list, move the direction arrow
to highlight INBOX and press Enter to read messages in your INBOX folder.
To view a mail message, use the arrow keys to highlight the message you want
to read and press Enter. When you finish reading it, there are many
commands you can issue to handle the message or to continue reading mail,
including:
| d |
Marks the message to be deleted. The message will
appear in the message list marked with the letter D, but
it will not be deleted until you quit Pine. You can
also type u to undelete a message. Typing
x will immediately delete all messages marked
for deletion. |
| n |
Go to the next message. |
| p |
Go to the previous message. |
| r |
Reply to the message (send mail back to the
person who sent mail to you). |
| i |
Return to the index of messages for a folder. |
Remember that related commands are always printed at the bottom of the
screen. They are available to you whether you are using the list of messages
or viewing individual messages.
Sending Mail
Choose Compose Message from the Main Menu, or
type c from almost any screen in Pine. Type the
address of the person(s) you'd like to send mail to on the
To line, and a brief subject for the message on the
Subject line. Press Enter or the arrow keys
to move from line to line.
Note: The editor used in Pine for composing messages is Pico.
For more information on Pico, refer to Using the
Pico Text Editor.
When you press Enter at the end of the Subject line, you
will be in the message content area, (i.e., the area below the
message headers). In the message content area, it is not
necessary to press Enter at the end of every line because the
word wrap feature (similar to a word processing tool) does not require
you to press Enter at the end of each line. Your messages will be
easier for other people to read when you use this method. You should also
press Enter twice at the end of every paragraph so that the paragraphs
are separated by blank lines. Tip: Keep each paragraph fairly short.
There are many editing commands you can use. They are shown at
the bottom of the screen as letters preceded by the caret
(^) symbol. The caret indicates that you must use
the Control key. For instance, after you create your
message, you will want to send it. At the command list at the
bottom of the screen, you'll see ^X next to
Send. This command is therefore known as
Control-x. To type it, press and hold down the
Control key and then type x - the same way
you would use the Shift key to type an uppercase
character. Once you type ^x, a prompt is
displayed to confirm the command. You can then type
y (yes) to send the message; or you can
type n (no) to return to the message and continue
editing. If you decide you'd rather not send the message, type
^c (Cancel) instead of ^x.
A quick way to send a mail message to someone is to type:
pine person's-address
at a Unix command prompt. You will be placed directly in
the Compose Message screen. Once you send the message, you
will exit the Pine program and return to the Unix command prompt.
Note: OIT directly mails users with information about
the status of their TerpConnect or GRACE accounts. It is important to read
your e-mail!
Saving a Message
Unless you delete a message, it will remain available to you in your INBOX.
If you find that you are keeping many old messages, it is more convenient to
organize them into separate folders. This is done by saving the
message.
To save a message you have just read, type s. Pine will
ask which folder you want to save the message into. Type a name that will
remind you of the content of the message; for example, you might want to save
messages from your professors into a folder titled work, and messages
from your friends into a folder titled friends. If you do not indicate
a folder name and press Enter instead, your message will be saved in
the default folder titled saved-messages and the message will be marked
for deletion from your inbox when you expunge messages or exit from Pine. If
saved-messages has not been created, you must type y
(yes) to confirm the creation of this folder before saving messages within
it.
To reread these messages later, go into the Folder List by typing
l (ell), or choose Folder List
from the Main Menu. Then, use the arrow keys to select the
folder you saved the message into, and press Enter. To get
back to your incoming mail, go into the Folder List and
he INBOX folder.
Quitting Pine
Type q to quit Pine. A prompt is displayed to
confirm your exit from Pine. Type y (yes) to
confirm your exit. If you have marked any messages for deletion,
a prompt is displayed to confirm that you want to expunge
them, which deletes them completely. If you type
y, they will be completely deleted; if you type
n (no), the deleted messages will still be
available next time you use Pine (although they will still be
marked with the letter D). Unless you think you have made
a mistake in deleting a message, y is the
preferred choice.
Once you know the basics of the Pine program, you should be
able to figure out most of the other features of Pine for
yourself. Don't forget to type ? for help
whenever you need to know how to use a command or which command to
use.
You can learn more about Pine on-line at
http://www.helpdesk.umd.edu/topics/applications/email/pine.
Troubleshooting Your TerpConnect or GRACE Account
TerpConnect and GRACE account space is limited. Each user is assigned a
disk quota. This quota is an indicator for the number of files you have
created and the limit on space that you can use. If you exceed this amount,
you will be unable to access any more space until you have deleted some files.
If you log in to your account and get one of these messages, your
account may be over quota:
- your disk space is exceeded
- your mailbox is read-only
- new message move failed
Over Quota
To check if you are over quota:
- Login to your account with a terminal session (see
Connecting to Your TerpConnect or GRACE Account).
Make sure you are not logged in to the account with a mail client
(such as Thunderbird, SeaMonkey, or Outlook Express).
- At the prompt, type:
quota
This displays how much space you are using. If you are using more
than 90% of your quota, you should clear space in your account.
- Clear any temporary files by typing:
clearcache
If you are still over quota, go to the next section to
determine which directories and files are causing problems. You
can then delete any unwanted items.
Your account has 3 main directories: pub, home,
mail. This section looks at the pub and home
directories. The third directory, mail, stores your Inbox
and messages waiting to be delivered.
- The pub directory is where public files for your website are
stored (www.wam.umd.edu/~loginname or
www.glue.umd.edu/~loginname).
- The home directory stores files or directories you've created,
and mail folders such as Sent Items and Trash.
Deleting Files in Pub
To delete files in your Pub directory:
- While connected to your account using a terminal program, list
the files and directories in your pub directory by typing:
cd ../pub
then list the files from smallest to largest by typing:
du -sk * | sort -n
- If you see a file or directory you no longer need, remove it by typing:
rm filename
or
rm -rf directory
Deleting Files in Home
To delete files in your Home directory:
- Return to your home directory from the pub directory by typing:
cd
then list the files in order of smallest to largest by typing:
du -sk * | sort -n
To delete files, follow the instructions in step 2.
- If you see mail folders (Sent Items or
Trash) use the Unix mail program to delete messages (see
Using Unix Mail). If you have a directory
titled mail or Mail in your home directory,
they may contain mail folders. To move into one of those mail
directories type:
cd Mail
or
cd mail
- To obtain a list of folders within a mail or Mail
directory type:
du -sk * | sort -n
Using Unix Mail
When you are over quota, the mail program you normally use may not be able
to delete messages. The Unix mail program allows you to delete messages in any
mail folder if you know the folder name.
To access your Inbox, from a command prompt (y, z) type:
Mail -f
To delete messages in other mail folders, use the same command:
- Mail -f Sent
- Mail -f "Sent Items"
- Mail -f personal
You will see a screen of messages with several columns. The left column
is the message number, followed by the sender, date and time, message size,
and subject.
Moving Around
Use commands at the Mail& prompt to move around the folder:
| h |
This lists the current page of messages |
| z |
Moves you to the next page of messages |
| z- |
Moves you to the previous page of messages |
Reading Messages
If you need to read an e-mail you can type the message number t the
Mail& prompt and press Enter. To return to the mail prompt
type q.
Deleting Messages
You can delete messages individually, in a range, or several at once:
| Command |
Example |
| d message# |
d 8 |
| d #-# |
d 10-18 |
| d # # # # |
d 2 9 14 22 |
Note: In most folders your first message will be a system email
with the subject of "DON'T DELETE THIS MESSAGE." You will want to leave that
message alone to avoid problems in the future.
At this point messages are marked to be deleted but they are not purged.
If you've mistakenly deleted a message, type x (exit) at the
Mail& prompt. To exit and purge the deleted messages type
q(quit).
Check your quota again (Over Quota). If you are still
over quota contact the OIT Help Desk for
assistance.
Printing Your Work
Print Accounts are required for printing in all TerpConnect, and
many Departmental Computer Labs. A personal print account has
two parts: a Terrapin Express account and a computer-based print
account. You can obtain both parts at the Terrapin Express
Contract Office in the South Campus Dining Hall, room
1109. Opening a Terrapin Express debit account requires a minimum
deposit of $20. If you already have a Terrapin Express account,
you can obtain a print account from the OIT Help
Desk.
When using your TerpConnect account, you can print to a laser
printer in each of the OIT Computer Labs and to other designated
locations. Applications that have been configured to allow
printing, usually have a Print option available. If this
option is not available to you from a menu within the application,
you can use the qpr command followed by the
filename. This command can be typed from the Unix
prompt:
qpr filename
If you are on a Linux workstation in an OIT Computer Lab, the file will
print in the lab.
You can also specify a designated printer using the q option. For
example qpr -q printer-name filename would print
filename to the designated printer-name. Using this option
provides you with a means for printing to a printer other than the lab in
which you are working. This is also useful when you're logged into one of
the session servers for the TerpConnect or GRACE cluster.
|
OIT Computer Lab
|
Printer Name
|
|
McKeldin Library
|
mckeldin
|
|
Parking Garage II
|
pg2
|
|
Worcester
|
wor
|
|
CSS 3330 - Windows PC Lab
|
cscpc
|
|
CSS 3332 - Macintosh Lab
|
cscmac
|
|
A.V. Williams 1120
|
avw
|
In all OIT Computer Labs, and most other Departmental Computer Labs, a
print authorization dialog box will prompt you for a page estimate, your
print account number and password. The dialog box also notes the printer
to which your job will be directed and a queue name (to help you trace
your print job). Your printed copy is then sent to the laser printer you
selected.
You will be prompted for your print account number, password and page
estimate for remote access also. This is a sample of this dialog from a
typical TerpConnect Unix prompt:
y:~: qpr -q pg2 program1.c
Laser Print Cost Recovery Program.
Print Accounts are now required.
Charging now in effect, $0.10 per page
| Maximum pages [25]: |
Leave blank or enter a number |
| Authentication account: |
| Print account password? |
Note that nothing will appear on your monitor when you enter your
authorization account number and password. |
If your job exceeds available funds and you try to print, your job will
be aborted and you will receive a dialog box informing you that you have
insufficient funds. Visit the website
http://bank.umd.edu and transfer additional funds from your Terrapin
Express account to the print bank. You must provide your authorization
number and password when prompted.
Note: A list of queues is available on-line at
http://www.helpdesk.umd.edu/documents/0/180/.
Bad Copy Credit
Credit request forms are available at
http://www.helpdesk.umd.edu/documents/0/179/.
Credit is given for bad print copies caused by malfunctioning printers.
Credit is not given for poor formatting or editorial mistakes. (Samples
of bad print jobs are posted in labs.)
Credit requests will be processed within three working days of receipt.
Funds will be credited to your print account; no cash will be exchanged.
Credit must be requested within one month of the bad printout.
Note: You will never be asked to divulge your password in
order to receive credit for poor copies.
Unix File System
The Unix file system uses a tree structure. At the base of the tree
is the root. Rising from the root are a number of branches. These branches
lead to other branches and leaves.
In Unix, each branch relates to a directory; each leaf relates to a
file. At the base of the file system is a directory called root,
which is denoted by the slash (/). From this directory you can trace a path of
directories to any file in the system.
Each login name is assigned a home directory. This is your personal
workspace on the system. When you log onto the system, your default (preset)
working directory is your home directory. The home directory is set up as a
private directory; only the user who owns the home directory may see files it
contains.
A path describes the chain of directory branches which lead to a
particular directory (or file). Each directory name (and the final filename,
if any) in the path is separated from the others by a slash (/) and therefore
creates a pathname. For example, the /usr/users pathname
initiates from root, to the usr directory, then to the
users file (or directory).
Your working directory (or current directory) is the branch
where you are currently located within the file system; this is where Unix
will first look for files you wish to access or commands you wish to execute.
You can find the path to your current directory by entering the pwd
(present working directory) command.
A pathname that begins with / is an absolute path. It refers to a
precise file or directory starting from the root directory. A pathname
which does not begin with a / is a relative path and refers to a
directory or file starting from or relative to your current directory.
There are two directories that need further discussion. Your
current directory is called . (one period), pronounced "dot".
In any command that requires a directory name, the single period refers to
the current directory. The parent directory of the current directory
(the next level on the hierarchy) is called .. (two periods),
pronounced "dot dot".
Files and Directories
One of the benefits of having an account on the TerpConnect or GRACE
system is having a home directory where you can store
files. Inside this home directory, you can create any files you
choose, and you can create subdirectories to better organize
your files.
You can envision the way directories are organized in terms of
a family tree. All of the directories on the TerpConnect or GRACE
system are descendents of the root directory. The root directory is
indicated by a / (forward slash). Its children
include various subdirectories, one of which is your home
directory identified through your login name.
The hierarchy below starts with the root directory and branches off into
other subdirectories.
Note: Home is your home directory, where you start when you
log in. Pub is a directory in which you can make files public for the
use of others, mail is where your mail is stored IF you have
a departmental e-mail server, and backup is a directory leading
to on-line backups of your files.
Public, Home and Mail Directories
The public directory, /pub/login-name, is a special directory
established for you to share your files with others. When you put files under
this directory, they will be viewable to everyone. The
/pub/login-name directory is where your web pages should be
placed.
An associate to the public directory is your home directory,
/homes/login-name. Files in this directory are private. This is
where you will find all of your files and directories.
Besides knowing which mail program you are using to send and read mail,
you will notice that mail is stored on your account under the
/mail/login-name directory.
Changing Directories
To change your current directory to another directory, use the
cd command. For example, enter:
cd pathname-of-the-directory
For example, when using the file structure pictured above, you could move
into the friends directory by using the following command:
cd /home/letters/friends
If the directory that you are changing to is further down the same path as
your current directory, you only need to specify the path leading to the
directory.
For example, if you wished to access the toMom directory, and your
current directory was letters, you would only have to type:
cd toMom
To get back to your home directory, simply type:
cd
Specifying a Directory Pathname (3 Ways)
The cd command is used to change to another
directory. You can only change into a directory that is the
parent or child of (immediately above or below) the directory you
are currently in, unless you specify the pathname to the
directory you wish to change into. A pathname is a way of
representing the directory hierarchy to the file you are
accessing. Slash (/) symbols are used to separate
directories. For example:
/users/your-loginname/home/letters/toMom
First Way: Relative to the Directory You Are in Currently
If you are currently in your home directory (as you are
when you log in), and want to change into a directory you created
called toMom you would type:
cd letters
cd toMom
or you could type:
cd letters/toMom
In this example, letters is a directory that is the
child of the home directory you are currently in. If you
were already in the directory toMom, and wanted to change
into the directory friends, (its sibling), you would change
into the parent directory letters before you would change
into friends. To do this, you would use ..
(pronounced dot dot). So, you could type:
cd ..
cd friends
or you could type:
cd ../friends
Second Way: Relative to the Root Directory
To specify a path relative to the root directory, use the slash
(/) symbol. If you are currently in your home
directory, and want to change into the directory of a user whose
login name is jdoe, you could type:
cd /
cd users
cd jdoe
or you could type:
cd /users/jdoe
Note that if there were a jdoe, you would not be able to
change to this directory unless you have been given permission
using a system called AFS. Others can't access your files
unless you specifically let them. Type man afs at
the command prompt for more information on this system or see The AFS File System.
Third Way: Relative to Your Home Directory
To specify a path relative to your home directory, begin the
path with the tilde (~) symbol. The tilde
indicates your home directory. This is useful when you are not in
your home directory (or you're not sure whether you are in your
home directory), and when you want to change to another
directory. To use the example in the previous section where you
wanted to change to the toMom directory, if you are not
sure if you are in your home directory, you may type:
cd ~/letters/toMom
which guarantees that your cd (change
directory) command is initiated from your home
directory. The tilde can also refer to someone else's home
directory when you follow it with that user's login name. For
example, instead of typing:
cd /users/jdoe/home
you can move to the jdoe/home directory by typing:
cd ~jdoe
Note: If you do not specify a directory when using the cd
command, you will return to your home directory.
Using Pathnames with Commands
Once you learn how to use these pathnames, you can use them
with any Unix command. If you want to edit a file titled
george.1 in the friends subdirectory, you could
change to that directory before issuing the command:
cd ~/letters/friends
pico george.1
or you could use the pathname as part of the command:
pico ~/letters/friends/george.1
Listing Files
To see a listing of the files in your current directory, use the ls
command.
ls
If there are files in a directory that you do not care to see
when you request a simple directory listing (ls), give those files
a name that begins with a period. Use the ls command with
the -a option to see a list of all files in the current directory
including hidden or dot files. (Unix options are usually preceded by a
hyphen.)
ls -a
Such files are hidden because the simple ls command will
not show them. Type ls -l to see information about your files,
including the size and last date of modification.
Creating and Deleting Directories
To create a directory, use the mkdir command. This command
creates a subdirectory under the current directory. For example, to
create a directory named project1 you would type:
mkdir project1
To delete a directory, use the rmdir command. When you
use the rmdir command, you must delete all of the files in the
directory before you can delete the directory itself. For example, to
delete a directory named project1 (under your current
directory) you would type:
rmdir project1
Deleting Files
To delete an individual file, use the rm command. For
example, to delete a file named test.data, you would type:
rm test.data
If you type rm -i test.data, the system will prompt you to verify
the removal of the file. To delete all files in a subdirectory and the
subdirectory, type \rm -rf directory. Use caution when using
the -rf option!
If you accidentally create a file with a name that has garbled
characters in it, the rm command may not be able to delete
it. To delete such a file, you may be able to quote the offending
character by prefixing it with a backslash (\). If this doesn't work,
first type ls -i to find the inode number of your file
(the inode number is a unique identifier for
the file). Make sure that your current directory is the directory
containing the file you want to delete, then type the following command to
remove the file (don't forget the backslash at the end of the line):
find . -inum inode-number -exec rm -i {} \;
where inode-number is the actual inode number of the file you are
deleting. You will be prompted to verify that you really want to delete the
file before it is removed.
File Recovery
If you are in the AFS file system, your backup directory can also be
accessed from
/users/loginname/backup/home.
To gain access to the most recent backup, type:
cd /users/loginname/backup/home
If you need to recover a file, do so as soon as possible. Since
a new backup is performed every morning at 12:00 a.m., the
previous day's backup is lost. If you do not recover a lost file before
the next backup, it will have to be restored from tape.
Note that these backups are a read-only copy of your
files; while they have the same ACL (Access Control List) as your
own files, they are in a read-only volume and can not be modified
or deleted. You cannot directly write into the backup volume to
add additional files.
If you are in NFS (Network File System), contact your local lab manager
or the OIT Help Desk to see about file
recovery.
Also note that there may be times when your backups are unavailable due to
storage and maintenance requirements. Never intentionally delete or
modify your files expecting later to recover them from the backups.
Basic Unix Commands
There are a number of Unix commands of which you should
learn. Type these commands at the command prompt.
| cat filename [filename...] | Displays the
contents of a file or files on the screen. |
| cd
directoryname | Change directories into
directoryname. |
| cd .. | Change to the parent of the directory
from the directory you're currently in. |
| cd | Change to your home directory. |
| cp filename1 newname | Copy
filename1 to newname. This command can be used to copy
the contents of a file into another file with a resulting newname.
|
| cp filename directoryname | Copies
a file into another directory keeping the same file name for both
copies. |
| chfn | Change the information revealed about you
when someone fingers you. |
| du -sk | Displays a summary of disk usage
instead of a comprehensive listing. |
| file filename | Indicates what specific
file type file is. |
| finger username | Get information
about username. This could be a user on the TerpConnect system
or on another computer elsewhere. |
| less filename [filename ...] |
Displays the contents of a file or files one screen at a time;
press the Spacebar to continue one page (screen) at a time;
Return to advance a line at a time; q to stop or ?
for help. |
| ls | List the names of your files. |
| ls -a | List all of your files, including those
starting with a . (dot). |
| man commandname | Display help
text (a manual page) for commandname. Use the
spacebar to page down through the help, and q to
quit. |
| man -k keyword | Finds all manual
pages whose titles or descriptions mention keyword. |
| mkdir directoryname | Make
(create) the directory directoryname. |
| mv filename1
filename2 | Move filename1
to filename2. This command can be used to rename a file, or to
move it from one directory to another by giving a path for one or both
filenames. This command can also be used to rename directories using the
syntax: mv directory1 directory2. |
| mv filename directoryname |
Moves a file to another directory.
|
| passwd | Change your password. You will be
asked for your old password once and your new password twice. When
you type them, neither will appear. |
| pine | Starts MIME-compliant mail program.
Allows for binary attachments like word processing files. |
| pwd | Display the path to your current
directory. This is an abbreviation for "print working
directory." |
| qpr filename | Prints the file
filename to the default printer. |
| qpr -q printer filename |
Prints the file filename to a designated printer indicated as
printer. |
| quota | Used to display how much of your
allocated quota of 100,000 kilobytes (100 megabytes) have been used.
Note: The command fs listquota only works if you are in the
AFS file system on TerpConnect or GRACE. Not all TerpConnect users are in
AFS; some are in departmental NFS space. |
| rm filename | Remove (delete) the
file filename. |
| rmdir directoryname |
Remove (delete) the directory directoryname, providing the
directory is empty. |
| who | Displays who is currently on the
system. |
| w | Displays a list of users who are currently
on the system and what they are doing. |
| zwrite userid | Allows interactive
communication with another user. To send message type Ctrl-D on a
new line. |
Redirecting Input and Output
Most of the commands listed above produce output at your workstation. Some
take input from the keyboard. In Unix you can use special characters to
redirect input and/or output to files and other programs. These characters
are used to redirect input/output:
|
<
|
Take input from a file
|
|
>
|
Send output to a file (create/overwrite)
|
|
>>
|
Append output to a file (create/append)
|
|
| | Send (pipe) output of one command to the input of
another command
|
Some examples of these characters in use are:
|
mail johndoe < mailfile
|
Sends the file mailfile as a mail message to user johndoe.
|
|
sort < unsorted > sorted
|
Sorts the file unsorted and stores the output in the file
sorted.
|
|
cat listing >> temp
|
Appends the file listing to the end of the file temp.
|
|
who | more
|
Displays the users on the system a screen at a time.
|
Wildcards and Other Special Characters
Special characters may be of some use: * (asterisk), ?
(question mark), and ; (semicolon).
The * and ? are called wildcard characters. They can
be used for pattern matching when issuing commands. The * matches any
number (0-N) of characters. For example, if you were to issue the command
rm *, the * would match any file name in your current directory
and all of the files in the directory would be deleted with the exception of
hidden files. Use caution when using the asterisk to remove files. If
you instead typed the command rm *.c, only files ending in .c
would be deleted. Remember, once you remove a file it is gone forever,
and can only be restored from backup.
The ? matches any single character; e.g., if you were to type the
command cat prog? any file named prog followed by a single
character would be printed to the screen. Files named prog1,
proga, and prog- would all match prog? and be printed;
files named prog or prog23 would not match prog?.
There are exceptions for using the * and ? when referring to
hidden files. Hidden files begin with a dot. For example, .cshrc is a
hidden file. For these types of files, the cat prog? command mentioned
above will not work if the filename begins with a dot; you must include the
dot as a part of the command (For example, cat .prog?).
The semicolon can be used to separate multiple commands entered on the same
line. For example:
cd datadir; cat test.data
Job Control - Running Programs in the Background
A final useful special character is & (ampersand),
which is used for job control. If you want to start working on
something else while another command is being processed, you can do
so by placing an & after the command. This is called placing
a command in the background. For instance, if you wish to remove a
large directory of files before you begin to work on a different
project, you could type:
rm -r largedirectory &
If you've already initiated a command, you can pause the execution of this
command by typing a Ctrl-z. You can then resume execution of the paused
command in the background by typing bg. Commands paused with
Ctrl-z can also be brought to the foreground; that is,
they can be brought back to normal execution rather than being placed in the
background. To restart normal execution of a job paused with Ctrl-z,
type fg.
If you have several jobs in the background, the fg command will
restart the job most recently paused. To restart any of the other commands
that are paused, you must know its job number. The jobs command will
list the job number and state of any background jobs. For example, here is the
output from the jobs command for a user who has paused a vi
editing session, paused the man command and has a C program
compiling in the background:
jobs
[1] + Stopped vi prog2
[2] - Stopped man rn
[3] Running cc -g prog1.c
The job number is the number listed in brackets. To restart a
command (other than the most recent), you use the fg command like
this:
fg %job-number
To restart the vi command in the above example, you would type:
fg %1
Be aware of processes (programs and commands) that you place in
the background. Certain programs that wait for user input, such as editors
or the lisp interpreter, will continue running if left in the
background.
You can determine whether or not you have left any processes
running by using the ps (process status) command. This command displays
information concerning every process running that belongs to your
login name. For example, here is the output from the ps command; a
lisp process has been suspended:
|
PID
|
TTY
|
S
|
TIME
|
CMD
|
|
18816
|
ttyp4
|
S
|
0:04
|
-csh (csh)
|
|
18834
|
ttyp4
|
T
|
0:00
|
lisp
|
|
18836
|
ttyp4
|
R
|
0:00
|
ps
|
PID indicates the process id number of each process. S
indicates the state of the process (in the example above, S and
T indicate paused or waiting processes and R indicates a
running process). CMD indicates the command which invoked the
process. In the above command, csh indicates the shell and ps
indicates the command that was executed.
To terminate a process, enter the command:
kill pid
where pid is the process id number of the process you eliminate.
If you eliminate -csh, you will log yourself off. Therefore in the
example above, to terminate the lisp process, enter the command:
kill 18834
If the kill command doesn't terminate the process, try using
the kill -9 command, which is a more extreme version of the
command, and should terminate any process. You should always use
the kill command first, as the kill -9 command doesn't give
the program a chance to do any cleanup before it exits.
Occasionally, you might find that you are logged on more than
once. You can tell this either by issuing the w command to see who
is logged onto the system or by doing the ps command and
seeing a csh process active for more than one TTY
(terminal) line at the same time.
Below is a sample of the output from the ps command if
you were logged on more than
once:
|
PID
|
TTY
|
S
|
TIME
|
CMD
|
|
18872
|
ttyp0
|
S
|
0:03
|
-csh (csh)
|
|
18901
|
ttyp5
|
S
|
0:03
|
-csh (csh)
|
|
18917
|
ttyp5
|
R
|
0:00
|
ps
|
The above shows that a user has a csh process active on
ttyp0 and ttyp5. After you determine the csh you are
using, use the kill command to abort the additional process. Use
the tty command to determine your current TTY line:
tty /dev/pts/6
Additional processes that are not associated with your current
TTY can be aborted; therefore, using the sample output of the
ps command and the above output of the tty command,
you would kill process 18872 because it is not associated with your
current tty (i.e.,ttyp5).
You can also kill a job with the command:
kill %job-number
Editing Files
OIT Unix systems have several editors available for creating
new and editing existing files. The three most popular editors are
Pico, Emacs and Vi.
Pico is the easiest text editor to use. This visual
editor displays a command list at
the bottom of the screen for performing basic tasks such as justifying
text, cutting and pasting text and spell-checking a file. For more
information on the pico editor, refer to
Using the Pico Text Editor.
Emacs is a very powerful editor. It allows you to use and customize
a very large set of commands. Emacs has environmental modes for basic
text editing, editing C program files and editing Lisp program
files. For more information on the emacs editor, refer to
Using the Emacs Text Editor.
Vi is an editor that is almost universally available on
Unix-based machines. It is available on all of the Unix systems maintained
by OIT. For more information on the Vi editor, refer to
Using the Vi Text Editor.
Changing Your Account's Environment
When you establish your TerpConnect or GRACE account, a number of
default (preset) configuration files govern various parameters, window
size and placement, and where to look for commands. You can alter these
defaults by editing various hidden files (dot files) in your home
directory:
|
.environment
|
- for modifying environmental variables and conditions
|
|
.path
|
- for modifying the search path used when executing commands
|
|
.aliases
|
- for setting user command aliases
|
|
.cshrc.mine
|
- for setting other user shell variables not mentioned above (do not
edit .cshrc)
|
|
.startup.X
|
- for setting startup commands in X-Windows connections |
|
.startup.tty
|
- for setting startup commands in text-only connections |
However, should you want to return to default status again, run
the original defaults script program again by typing
/usr/local/scripts/newdefaults
at the Unix prompt. This will return your account to its default settings.
Previous configuration modifications will be moved to filename-date;
whereas, filename is the file you modified and date is the date
of the modification. For example, .path-27-11-96 would
represent the November 27, 1996 version of .path. It is also important
to note that after you type /usr/local/scripts/newdefaults at
the Unix prompt, the .aliases file and any .mine (.cshrc.mine,
logout.mine, etc.) files will not be changed.
Internet Services
You may have heard of Internet services, such as FTP, mailing
lists, and the World Wide Web. These services are described below.
SFTP (Secure File Transfer Protocol) is used to transfer files from
one computer connected to the Internet to another computer connected to the
Internet. Both SFTP and SCP (Secure CoPy) are available for use on TerpConnect
and GRACE.
Note: For more information about using SFTP and Listserv, refer to
Transferring Files with SFTP or SCP and
A Basic Guide to Listserv.
Note: Non-secure connections (telnet, ftp) are not allowed to
TerpConnect or GRACE hosts.
Mailing lists are similar to the newsgroups in Usenet
News, but the articles appear in your e-mail, and you submit your
own articles via e-mail. You can find a list of publicly
accessible mailing lists in the newsgroup news.lists. You
typically subscribe to a mailing list by sending an e-mail message
to an automatic subscription mechanism.
A Listserv list is an example of an automatic
subscription mechanism. The address to use to send e-mail to will
be given in the mailing lists. A typical mailing list is the
fyi mailing list operated at the University. To subscribe
to this list you would send mail to:
listserv@listserv.umd.edu
In the body of the e-mail message, you would write:
subscribe fyi firstname lastname
You would then receive a confirmation message back telling you
that you had been added to the mailing list and giving information
about the list. When you read or hear about a mailing list, it is
very important that you find out what e-mail address to send your
subscription request to; otherwise, you will not be able to
subscribe.
The World Wide Web allows you to retrieve information
that other Internet users have made available. The web uses
hypertext and by clicking on a hypertext link you
can be connected to a document in another information database
located in another part of the world. You can look at a
screen of information and click on words and pictures that
will link you to text, graphics, and sound files. A web page may
connect to information from numerous sites all over the
world. You can connect to the web with a graphical interface
web browser like SeaMonkey, Firefox or Internet
Explorer.
Note: For more information on the World Wide Web, refer to
A Pocket Guide to the World Wide Web.
Getting Help
One feature of Unix is that system documentation is available on-line. If
you need help with a particular command (e.g., identifying appropriate usage
or syntax), type:
man command
Invoking the man command displays the relevant Unix reference manual
pages. If you are uncertain about features associated with any command, review
the manual pages.
The apropos command lists all on-line manual sections that
contain instances of given keywords in their title. The format for
apropos is:
apropos keyword
One point of contact is the OIT Help Desk.
There are two ways you can contact this resource:
Note: The hours listed above are the usual hours during the semester.
Please check with the Help Desk for their current hours, especially at the
beginning or end of the semester, or during the summer.
You can also submit a problem report to the
OIT Help Desk by typing request at the Unix command
prompt.
The AFS File System
The TerpConnect and GRACE systems use AFS, a network file system that allows
the individual terminals to access files on TerpConnect and GRACE servers
across the University. AFS is TerpConnect and GRACE specific. It uses a
robust, distributed model that provides user authentication and
an extensive set of file access methods and protections. For more
information about AFS, visit
http://www.helpdesk.umd.edu/documents/1/1222.
Note: Most, but not all TerpConnect accounts are on the AFS
system. Some departmental accounts can have the home directory in
local departmental NFS space.
Acceptable Use Policy
Please take a look at the University of Maryland's Computer
Acceptable Use Policy. It can be found at the following URL:
http://www.nethics.umd.edu/aup/.
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