Euclid Frequently Asked Questions

Welcome to Euclid! This document is intended to help you use the facilities of this computer. It is arranged in a question-and-answer format.

Contents

There are five options.

First, please read this document carefully to see if your question is already answered. If you can't find the answer, then send an email to the account requests@euclid.trentu.ca. To do this from Euclid, type:

pine requests

Alternately, if it is urgent, you can phone me at (748-1011)-1293.

Connect Euclid using the Secure File Transfer Protocol program SFTP. (We have blocked FTP access to Euclid because FTP is not secure.)

It is very important, when you log in for the first time, to change your password immediately. The `initial' password you were given is not secure.

To change your password, type passwd. You will see:

Changing password for yourname

(current) UNIX password:

Type your current password, hit return, and then enter your new password. You will have to type it a second time for confirmation.

Remember that the security of your account is not just your problem ---it is everyone's problem. If your security is compromised, then everyone's security is potentially compromised.

You should choose a password that is hard to guess. Your password should be at least 8 characters long, and a mixture of numbers and upper and lower case letters.

• Never use a real English word (eg. `esoteric'). It can be easily guessed by a `dictionary' program.

• Don't use a real word in any other language, either, especially not one you are known to speak. For example, if you speak Spanish, do not use `contrasena' as your password. It can be easily guessed by a Spanish `dictionary' program, if someone knows you speak Spanish.

• Never use a piece of `obscure' mathematical jargon, or a mathematician's name (eg. `homology' or `Riemann'). It can be even more easily guessed by a math-specific `dictionary' program.

• Never use a piece of personal information (eg. your husband's name, your birthday, etc.). It can be guessed by someone who does a little bit of background research on you.

• Never use `clever' passwords, like `PASSWORD', `drowssap', `secret', `crypto', `keepout', `qwerasdf', `opensesame', `3141592' or `12345678'. (``I bet they'll never guess that one.'') Actually, they will.

• Never use the same password for more than one computer account. If someone breaks into one computer system, they will get access to all your accounts.

• Never, ever, email anyone your password. Email is not secure unless it is encrypted. If you want to tell someone your password through email, express it obscurely in the form of `shared secret'. For example, if your password is `314lebesGUE', then describe it as, ``The first three digits in the decimal expansion of arccos(-1), followed by the last name of the inventor of modern measure and integration theory, with only the last three letters capitalized (eg. `123johnSON').'' If you don't `share' any secrets with this person, you'd better phone them instead. (If you don't share any secrets and you don't know their phone number, why are you giving them your password?)

Files are digital repositories of information. Each file contains some self-contained body of information: a document, an image, or a working computer program. You can imagine them to be the electronic equivalent of the books, papers, pictures, tools, or kitchen utensils that you leave lying around your house.

Directories are the virtual `spaces' where files reside. You can imagine each directory to be like a `room' in a vast mansion. The files `in' that directory are like the books, pictures, and tools you find in that room. You can inspect these objects (ie. `read' a file) or use these tools (ie. `execute' a program). You can also copy them, rename them, or move them to another location.

The directories are arranged in a huge tree, like a family tree. Each directory has one or more subdirectories (its `children') and also a single `parent' directory. This structure is called the directory tree. Wherever you are, you are on some branch of the directory tree.

Every person has a first name and a family name. Generally, their family name reflects their ancestry. In some cultures, the family name has the form `Bob son of John son of Brian son of William' etc. You address someone by their first name if you're close to them, and you use their family name if you are distant.

In the same way, each file has a filename (like its `first name') and path name which reflects its full `ancestry' in the directory tree. For example, consider a file named mywork.tex in the subdirectory Work of the home directory of a user named bob. The filename of this file is just mywork.tex. However, its full pathname is:

/home/bob/Work/mywork.tex

How you address a file depends upon its physical location relative to you. You need to specify enough of its pathname to draw a path from your current directory to the file's location. This is called a relative pathname. For example, suppose you wanted to read the file mywork.tex. If you were currently in the directory /home/bob/Work/, then you would type:

 less mywork.tex

If you were in the directory /home/bob/, you would need to type:

 less Work/mywork.tex

Suppose you were in another subdirectory of /home/bob/. For example, suppose you were in /home/bob/Funstuff/. You use the symbol `../' to mean `the parent directory to where I am now'. Hence, you would type:

 less ../Work/mywork.tex

If you were in directory /home/alice/, you would type:

 less ../Bob/Work/mywork.tex

If you were in directory /home/alice/Research/Stochastic/, you would type:

 less ../../../Bob/Work/mywork.tex

At a certain point, these relative pathnames can obviously become quite complex. An alternative is to use the absolute pathname of the file. You can do this from anywhere in the directory tree. Just type:

 less /home/bob/Work/mywork.tex

Finally, if you are the user bob, then a shortcut is available. No matter where you are in the directory tree, you can use `~' to refer to your home directory. Thus, you could type:

 less ~/Work/mywork.tex

Euclid translates this to mean ``less /home/bob/Work/mywork.tex'' Note that you could not do this if you were alice, because then Euclid would translate it to mean ``less /home/alice/Work/mywork.tex''.

When you log in, the place you find yourself is your home directory. All of your files are stored in your home directory, or in subdirectories of your home directory. Each user has their own home directory; The user alice has the home directory /home/alice/

When you log in using SSH, you interact with the computer by typing commands. The thing you are typing commands into is your login shell. Think of it as your `virtual body', which you use to move through the `space' of directories.

You interact with Euclid by typing `commands' into the shell. A UNIX command takes the form:

commandname -s1 -s2.... filename1 filename2 ....

Here, commandname is the name of a program to be executed, -s1 -s2.... are one or more `switches' which modify the behaviour of the program, and filename1 filename2... are the names of one or more files which the program is supposed to read as input, or transform in some way.

For example, to compress files, I use a program called gzip. To compress a file named `masterwork.tex', I would type:

gzip masterwork.tex

I can also use the `-v9' switch to specify `maximum compression'. Then I would type:

gzip -v9 masterwork.tex

Note: UNIX commands are case sensitive. Thus, the program gzip is not the same as a program named `Gzip'; the file named `masterwork.tex' is not the same as a file named `MasterWork.tex'; the switch `-V9' may not have the same effect as the switch `-v9'. The following commands do not mean the same thing:

gzip -v9 masterwork.tex

gzip -V9 masterwork.tex

gzip -v9 MASTERWORK.TEX

You use the cd (`Change Directories') command. If you are in the directory /home/bob/ and you want to go to the subdirectory /home/bob/Work, you type:

cd Work

If you are in the directory /home/bob/ and you want to go to the subdirectory /home/bob/Work/Research/Galois/, you type:

cd Work/Research/Galois

You use ` ../' to refer to the `parent' of the directory you are currently in. For example, if you are in subdirectory /home/bob/Work/ and you want to go to directory /home/bob/, you type:

 cd .. 

If you are in the subdirectory /home/bob/Work/Research/Galois/ and you want to go to the directory /home/bob/, you type:

 cd ../../.. 

If you are in the subdirectory /home/bob/Work/Research/Galois/ and you want to go to the directory /home/bob/Work/Research/Homology, you type:

 cd ../Homology 

If you are in the subdirectory /home/bob/Work/Research/Galois/ and you want to go to the directory /home/bob/Work/Teaching/Calculus, you type:

 cd ../../Teaching/Calculus

Finally, if you are the user bob, then a shortcut is available. No matter where you are in the directory tree, you can use `~' to refer to your home directory. Thus, you could type:

 cd ~/Research/Teaching/Calculus

Use the command ls (`LiSt'). This is a very powerful command. To see a short list of all files in your current directory, type

 ls 

ls Work

If you are in the directory /home/bob/ and you want to see the subdirectory /home/bob/Work/Research/Galois/, you type:

ls Work/Research/Galois

You use ` ../' to refer to the `parent' of the directory you are currently in. For example, if you are in subdirectory /home/bob/Work/ and you want to go to directory /home/bob/, you type:

 ls .. 

If you are in the subdirectory /home/bob/Work/Research/Galois/ and you want to see the directory /home/bob/Work/Research/Homology, you type:

 ls ../Homology

To see all files that begin with the word `linear', type:

 ls linear* 

To see all files that end with `.tex' type:

 ls *.tex 

To get a more verbose list, with information about the sizes, ages, and file permissions of all the files, use the `-l' option. Type:

 ls -l 

For example, suppose you were in the subdirectory /home/bob/Work/Research/Galois/ and you want to get detailed information about all the $L$_AT^EX files in directory /home/bob/Work/Research/Homology which began with the word `functor'. You would type:

 ls -l ../Homology/functor*.tex 

Use the cp (`CoPy') command. To copy the file stuff to a file named morestuff, type:

cp stuff morestuff

To copy the file stuff to a file named morestuff in the subdirectory Work/, type:

cp stuff Work/morestuff

To copy the file stuff to a file also named stuff in the subdirectory Work/, type:

cp stuff Work/

Use the mv (`MoVe') command. To rename the file stuff to morestuff, type:

mv stuff morestuff

To move the file stuff to a file named morestuff in the subdirectory Work/, type:

mv stuff Work/morestuff

To move the file stuff to a file also named stuff in the subdirectory Work/, type:

mv stuff Work/

To delete a file, use the command rm (`ReMove'). To remove the file stuff, type:

 rm stuff

To remove the file stuff in the subdirectory Work, type:

 rm Work/stuff

To remove a directory, use the command rmdir (`ReMove DIRectory'). To remove the directory Work/, type:

 rmdir Work

Note: The rmdir command will only work if the directory Work/ is empty. To remove all files (but no subdirectories) of Work/, type

 rm Work/*

To remove all (empty) subdirectories of Work/, type

 rmdir Work/*

Unfortunately, this will not remove any nonempty subdirectories. To destroy all files and all subdirectories of Work/, we use the `-R' (`recursive') option. Type:

 rm -R Work/*

Warning: Never, ever use the `-R' option with rm unless you are absolutely, absolutely sure of what you are doing. With a single keystroke, you may accidentally wipe out your entire filesystem. If you ever plan to use rm -R, then doublecheck that you have correctly specified the pathname. Then recite the Greek alphabet backwards, from omega to alpha. Then doublecheck again. Only then should you press RETURN

In particular, never, ever, ever type `` rm -R *'', unless you want to destroy everything in your current directory and in all subdirectories.

To view a text file named stuff, type:

 less stuff 

Pico is a very simple and basic editor, identical to the one found in the email program Pine. To edit a text file named stuff, type: pico stuff. To quit pico, type [CTRl]-X.

Help: There are two sources of help for pico:

Emacs is an extremely powerful editor (practically an operating system). Emacs has a graphical user interface and a text-based interface.

OpenOffice is an open-source clone of Micro$oft Office, and provides comprehensive word processing/spreadsheet/database capabilities.

 print stuff 

(it doesn't matter whether stuff is $L$_AT^EX, DVI, PostScript, PDF, etc.) To print the file stuff with single-sided pages, type:

 print1 stuff 

To print a rough draft of the file stuff for proofreading, type:

 printd stuff 

(this will save on toner). To pick up your print job, come by Marcus's office (OC 221.1). You should phone first (1293) to make sure he is in his office.

Note: You are welcome to use the printer as much as you want. However, please ask Marcus before launching extremely large print jobs (in excess of 100 pages). Also, please do not use the printer as a photocopier. Do not print the same file 80 times in a row. Photocopier toner is much cheaper than laserprinter toner, so using a laserprinter as a photocopier is a waste of money. It is also a waste of other people's time, because a laser printer is much slower than a photocopier, and it may take a full hour to print 80 copies, during which time no one else can use the printer. Don't do it.

Type: pine. Then follow the instructions.

Secure POP is one method for email retrieval. When using a secure POP mail reader (such as Outlook, Mozilla Mail, etc) one can retrieve the contents of their email remotely, and with better security than normal email readers. This means that you can access your Euclid email from home by setting up a secure POP compatible mail reader.

*NOTE* If you use POP mail from one computer, and then want to access your saved email messages from a different computer (on-campus, your office, etc) you will discover your inbox is empty. This is due to the fact that POP mail downloads your email from Euclid to your computers hard drive. For many users this is completely acceptable, if you are not one of these users, then read the section below on IMAP access, which does not delete your mail from the Euclid server.

Secure IMAP mail is another method of email retrieval. With Secure IMAP you can use an email client program (Netscape Communicator, M$ Outlook, etc) to interact with your Euclid email account. With Secure IMAP, when you download your email onto a computer, the emails are not deleted from the Euclid server. For example, this means that if you want to have access to your email from home via IMAP, and still be able to log into Euclid with SSH and use PINE, your emails will be visible from both locations.

Quick setup information for experts:

• POP/ IMAP Server name: euclid.trentu.ca
• SMTP Server name (IF setting up from your office): euclid.trentu.ca (otherwise use your ISP's smtp server)
• NOTE: you must select SSL Secure connection options for either POP or IMAP

Setting up POP in Netscape Mail (versions < 6.0)

Netscape Versions less than 6.0 may not use POP mail because these versions do not support secure password authentication. If you are using Netscape with a version number less than 6.0, please refer to the section on setting up IMAP mail, as netscape WILL support secure IMAP.

Setting up POP in Mozilla Mail (or Netscape versions >= 6.0)

1. In a Mozilla browser window, click the WINDOW menu
2. click the MAIL & NEWSGROUPS option
3. click the EDIT menu and choose MAIL & NEWS ACCOUNT SETTINGS

   At this point you will see a split screen window, on the left will be a list of options to choose from, and on the right will be associated text boxes and check boxes.

4. Select 'OUTGOING SERVER (SMTP)' from the left, and then
5. On the right, there is a box asking for SERVER NAME. In this box you will enter text depending on which of the following situations you are in:

   If you setting this up from your HOME computer, (ie: NOT your office computer) then in the box you must enter the address provided by your internet provider for SMTP Service. For example, if you are on Bell Sympatico, you would enter:

   smtp1.sympatico.ca

   or some variant thereof.

   If you are setting this up from your OFFICE computer, you may use the Euclid SMTP server PROVIDED that you have given the System Administrator your computers IP address. The address you would fill in your SMTP SERVER would then be:

   euclid.trentu.ca

6. Click the 'ADD ACCOUNT' button, and the "Account Wizard" will appear
7. Select the 'EMAIL ACCOUNT' option and click NEXT
8. Fill in your NAME and FULL email address (ie: joey@euclid.trentu.ca), and click NEXT
9. Select the POP Option and then enter: euclid.trentu.ca in the box asking for INCOMING SERVER; then click NEXT
10. Now enter your Euclid user name (the part before the @euclid.trentu.ca in your email address); then click NEXT
11. Now give this account a Nickname you can refer to (ie: Euclid Account); then click NEXT
12. Review the information presented, and the click FINISH.
13. Now, on the left of your screen, select the option 'SERVER SETTINGS'
14. On the right of your screen, check the box labeled "USE SECURE CONNECTION (SSL)"
15. Click OK
16. you are now ready to use Mozilla with your Euclid email account.

Setting up POP in Micro$oft Outlook Express

1. From your Outlook main screen Click the TOOLS menu, and choose ACCOUNTS
2. Click the ADD button, and then choose MAIL
3. Enter your full name and click NEXT
4. Select 'I already have an email address' and enter your euclid email address in the box.
5. Click NEXT
6. From the drop-down list, select POP
7. For the INCOMING MAIL SERVER, enter: euclid.trentu.ca
8. For the OUTGOING MAIL (SMTP) SERVER box, you will enter text depending on which of the following situations you are in:

   If you setting this up from your HOME computer, (ie: NOT your office computer) then in the box you must enter the address provided by your internet provider for SMTP Service. For example, if you are on Bell Sympatico, you would enter:

   smtp1.sympatico.ca

   or some variant thereof.

   If you are setting this up from your OFFICE computer, you may use the Euclid SMTP server PROVIDED that you have given the System Administrator your computers IP address. The address you would fill in your SMTP SERVER would then be:

   euclid.trentu.ca

9. Click NEXT
10. Enter your account name (the part before @euclid.trentu.ca your email address)
11. Enter your account password, then click NEXT
12. Click FINISH
13. you will now see a list of ACCOUNTS, near the bottom you should see 'euclid.trentu.ca'
14. Click this entry ONCE, and then click the PROPERTIES button
15. Click on the ADVANCED tab (near the top of the window)
16. You will see 'INCOMING MAIL ( POP3)' and then a checkbox which says 'THIS SERVER REQUIRES A SECURE CONNECTION (SSL)', check this box.
    **NOTE** DO NOT Check the box below 'OUTGOING MAIL (SMTP) **
17. Click OK
18. Click CLOSE
19. You are now ready to use Outlook Express with your Euclid email account.

My email program wasn't listed above!

If you aren't using one of the above email programs, you can still use the Euclid mail server. Consult your programs' documentation or website for information on how to configure it. Use the following as your server settings:

NOTE: Remember to select SECURE CONNECTIONS when configuring your software

• INCOMING ( POP or IMAP) Server Name:

  euclid.trentu.ca

• OUTGOING (SMTP) Server Name:
  • If you are in your office, type:

    euclid.trentu.ca

  • If you at home, use the SMTP server provided by your ISP. (ie: Bell Sympatico users would use: smtp1.sympatico.ca)

Quick setup information for experts:

• POP/ IMAP Server name: euclid.trentu.ca
• SMTP Server name (IF setting up from your office): euclid.trentu.ca (otherwise use your ISP's smtp server)
• NOTE: you must select SSL Secure connection options for either POP or IMAP

Setting up IMAP in Netscape Mail (versions < 6.0)

1. In a Netscape browser window, click the COMMUNICATOR menu
2. click the MESSENGER option
3. click the EDIT menu, and choose PREFERENCES

   At this point you will see a split screen window, on the left will be a list of options to choose from, and on the right will be associated text boxes and check boxes.

4. click IDENTITY on the left, and then on the right, enter at least your Full name and Email address (ie: myname@euclid.trentu.ca )
5. click MAIL SERVERS on the left, and then on the right click the 'Add..' button.
6. a new window will appear. In the GENERAL section, where it says SERVER NAME enter the text: euclid.trentu.ca
7. Select IMAP from the SERVER TYPE dropdown list
8. where it says USER NAME, enter your Euclid user name. (this is the part before @euclid.trentu.ca in your email address)
9. Click on the ' IMAP' tab (near the top of this window)
10. check the box labelled 'USE SECURE CONNECTION (SSL)'
11. Click OK
12. On the screen you sent back to, there is a spot which is asking for OUTGOING MAIL (SMTP) SERVER. In this box you will enter text depending on which of the following situations you are in:

    If you setting this up from your HOME computer, (ie: NOT your office computer) then in the box you must enter the address provided by your internet provider for SMTP Service. For example, if you are on Bell Sympatico, you would enter:

    smtp1.sympatico.ca

    or some variant thereof.

    If you are setting this up from your OFFICE computer, you may use the Euclid SMTP server PROVIDED that you have given the System Administrator your computers IP address. The address you would fill in your SMTP SERVER would then be:

    euclid.trentu.ca

13. For the option OUTGOING MAIL USER NAME, enter your Euclid user name (the part before @euclid.trentu.ca in your email address)
14. Click OK
15. You are now ready to use Netscape email with your Euclid email account.

Setting up IMAP in Mozilla Mail (or Netscape versions >= 6.0)

1. In a Mozilla browser window, click the WINDOW menu
2. click the MAIL & NEWSGROUPS option
3. click the EDIT menu and choose MAIL & NEWS ACCOUNT SETTINGS

   At this point you will see a split screen window, on the left will be a list of options to choose from, and on the right will be associated text boxes and check boxes.

4. Select 'OUTGOING SERVER (SMTP)' from the left, and then
5. On the right, there is a box asking for SERVER NAME. In this box you will enter text depending on which of the following situations you are in:

   If you setting this up from your HOME computer, (ie: NOT your office computer) then in the box you must enter the address provided by your internet provider for SMTP Service. For example, if you are on Bell Sympatico, you would enter:

   smtp1.sympatico.ca

   or some variant thereof.

   If you are setting this up from your OFFICE computer, you may use the Euclid SMTP server PROVIDED that you have given the System Administrator your computers IP address. The address you would fill in your SMTP SERVER would then be:

   euclid.trentu.ca

6. Click the 'ADD ACCOUNT' button, and the "Account Wizard" will appear
7. Select the 'EMAIL ACCOUNT' option and click NEXT
8. Fill in your NAME and FULL email address (ie: joey@euclid.trentu.ca), and click NEXT
9. Select the IMAP Option and then enter: euclid.trentu.ca in the box asking for INCOMING SERVER; then click NEXT
10. Now enter your Euclid user name (the part before the @euclid.trentu.ca in your email address); then click NEXT
11. Now give this account a Nickname you can refer to (ie: Euclid Account); then click NEXT
12. Review the information presented, and the click FINISH.
13. Now, on the left of your screen, select the option 'SERVER SETTINGS'
14. On the right of your screen, check the box labeled "USE SECURE CONNECTION (SSL)"
15. Click OK
16. you are now ready to use Mozilla with your Euclid email account.

Setting up IMAP in Micro$oft Outlook Express

1. From your Outlook main screen Click the TOOLS menu, and choose ACCOUNTS
2. Click the ADD button, and then choose MAIL
3. Enter your full name and click NEXT
4. Select 'I already have an email address' and enter your euclid email address in the box.
5. Click NEXT
6. From the drop-down list, select IMAP
7. For the INCOMING MAIL SERVER, enter: euclid.trentu.ca
8. For the OUTGOING MAIL (SMTP) SERVER box, you will enter text depending on which of the following situations you are in:

   If you setting this up from your HOME computer, (ie: NOT your office computer) then in the box you must enter the address provided by your internet provider for SMTP Service. For example, if you are on Bell Sympatico, you would enter:

   smtp1.sympatico.ca

   or some variant thereof.

   If you are setting this up from your OFFICE computer, you may use the Euclid SMTP server PROVIDED that you have given the System Administrator your computers IP address. The address you would fill in your SMTP SERVER would then be:

   euclid.trentu.ca

9. Click NEXT
10. Enter your account name (the part before @euclid.trentu.ca your email address)
11. Enter your account password, then click NEXT
12. Click FINISH
13. you will now see a list of ACCOUNTS, near the bottom you should see 'euclid.trentu.ca'
14. Click this entry ONCE, and then click the PROPERTIES button
15. Click on the ADVANCED tab (near the top of the window)
16. You will see 'INCOMING MAIL ( IMAP)' and then a checkbox which says 'THIS SERVER REQUIRES A SECURE CONNECTION (SSL)', check this box.
    **NOTE** DO NOT Check the box below 'OUTGOING MAIL (SMTP) **
17. Click OK
18. Click CLOSE
19. You are now ready to use Outlook Express with your Euclid email account.

My email program wasn't listed above!

If you aren't using one of the above email programs, you can still use the Euclid mail server. Consult your programs' documentation or website for information on how to configure it. Use the following as your server settings:

NOTE: Remember to select SECURE CONNECTIONS when configuring your software

• INCOMING ( POP or IMAP) Server Name:

  euclid.trentu.ca

• OUTGOING (SMTP) Server Name:
  • If you are in your office, type:

    euclid.trentu.ca

  • If you at home, use the SMTP server provided by your ISP. (ie: Bell Sympatico users would use: smtp1.sympatico.ca)

1. Log into your Trent mail account.
2. Click on the `Options' icon. It looks like this: , and is the middle of the three icons you see at the top of your browser window.
3. A subsidiary window will open, called `Novell WebAccess Options'. It looks like this:

   

4. Click on `Rules'. You should then see this:

   

5. Click on the checkbox that says `Vacation'. Change it to say `Forward'.
6. Click `Create'. You will then see the following window:

   

7. Type `forward' in the `Rule Name:' input box.
8. Type `myname@euclid.trentu.ca' in the `To:' input box. You should now see this:

   

9. Click `save'. You will see a warning saying:

   You have not defined a rule condition. If a condition is not defined, this rule will apply to ALL new messages received. To continue, save this rule with or without a condition.

10. Ignore this. Click `save' again.

Create a file in your home directory called .qmail. This file should contain a single line of text: your other email address. For example, if you wanted mail forwarded to myname@trentu.ca, then the .qmail file should simply say:

myname@trentu.ca

1. Press S for SETUP.
2. Press D for DIRECTORY.
3. Press A for ADD.
4. Press ENTER to add text into the first field.
5. Type: gwmail.trentu.ca .
6. Press ENTER .
7. Hit E to quit.
8. Hit Y to save.
9. Again, press A for ADD.
10. Again, press ENTER to add text into the first field.
11. Type: netmail.trentu.ca.
12. Again, press ENTER.
13. Again, hit E to quit.
14. Again, hit Y to save.

When you go to the Address Book in pine, you will see:

   .addressbook
  Personal AddressBook in .addressbook
                                        
    netmail.trentu.ca
  Directory Server on netmail.trentu.ca

    gwmail.trentu.ca
  Directory Server on gwmail.trentu.ca

Choose gwmail.trentu.ca to search for the email address of any Trent faculty member. Choose netmail.trentu.ca to search for the email address of any Trent student member.

Spam is unsolicited `junk' email. Some of it is advertising, some of it is email viruses, and some of it is just harassment.

Spam is created by sending mail to to huge `mailing lists'; these lists are automatically generated by simple computer programs. The best way to avoid spam is to keep your name off these lists as much as possible. Since they are generated by machines, they are not impossible to fool. In particular:

• Do not correctly fill out the `email' box in most web-based forms, except from companies that you trust. Reputable companies usually have a checkbox saying, `I do not wish to receive electronic promotional material' (or words to this effect). Make sure you have correctly checked this box.

• Do not post your correct email address on any webpage in unadulterated form. For example, it would be unwise to put the following in your webpage: For more information, send mail to <a href="mailto:myname@euclid.trentu.ca"> myname@euclid.trentu.ca</a>

  Spam-generating computer programs constantly scan the Web, looking for exactly this kind of advertisement. Instead, try something like:

  For more information, send mail to <a href="mailto:NO_SPAM_PLEASE_myname(at)euclid(dot)trentu(dot)ca"> <font>myname</font>@<font>euclid</font>.trentu.ca</a>

  The `<font>' tags do nothing, and are invisible; but they confuse the computer. The `NO_SPAM_PLEASE', `(at)', and `(dot)' create enough `noise' in the email address to fool most computer programs, but a real human could probably still figure out your correct address. If they are too stupid to figure out your real address, then you probably don't want to get mail from them anyways.

• Never, ever reply to spam. Do not send rude one-line messages. Do not send polite, carefully worded letters requesting removal from mailing lists. It is worse than a waste of time: you are providing the spammer with valuable information that a real live human lives at the other end of this email address.

How to spot spam: The following warning signs suggest that an unopened peice of mail is spam:

• Unfamiliar sender: It is from someone you've never heard of, who has a strange sounding email address from a large public email server (eg. `bif@aol.com').

• Strange subject line:

  • Lurid: eg. `HOT JAPANESE LASS' or `Enlarge your penis'.

  • Overly friendly (from total stranger), eg. `I love you', `Be my friend', `Hey! Great joke!'.

  • Bizarre `Re:' tag: for example, `Re:radon'

  • Panic-inducing: eg. `Warning!', `Your Password', `URGENT! Reply immediately'

  • Sentence fragment (usually randomly culled from your webpage). eg: `Re: This page last updated' or `Re: not a stationary stochastic'.

• Huge file size (eg. 128K) from total stranger. Usually this is a virus.

Don't worry about Euclid being `infected' by a virus. This is a UNIX system, and we don't get viruses. You should be concerned about the following:

• If you are running Micro$oft Windows(c) at home, and you are reading your mail using Micro$oft Outlook(c), then you are vulnerable. Do not open suspicious attachments.
• Even if you are not vulnerable, your friends may be. To avoid inadvertentyl affecting Micro$oft -using colleagues with a virus, never forward large pieces of spam email. If you receive this kind of spam, delete it immediately.

All of your webpages will be visible at the URL euclid.trentu.ca/yourname/. For example, suppose the user named alice created a file called research.html in her www/ directory. To see it, you would send your browser to

 
http://euclid.trentu.ca/alice/research.html

The file `index.html' is always the `default' file in any directory. For example, suppose alice created the directory www/Teaching/, and then created the file www/Teaching/index.html. To see it, you could go to

 http://euclid.trentu.ca/alice/Teaching/index.html

 http://euclid.trentu.ca/alice/Teaching/

GNUPlot is a simple graphing program which allows you to plot curves and surfaces in two or three dimensions. GNUPlot is not as sophisticated as MAPLE or Maxima, but has the advantage of being small, efficient, and relatively simple to use.

To run GNUPlot from a shell, type: gnuplot. To quit GNUplot, type: `quit;'.

Help: There are three sources of help for GNUplot:

Xcalc is a scientific calculator with a graphical user interface that emulates a TI-30 or HP-10C pocket calculator.

To run Xcalc from a shell, type `xcalc &'.