| 11. Usage | ||
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| 11. Usage | ||
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This section gives a brief overview of facilities of general interest on the Unix systems not previously discussed in this document. It discusses both facilities you need a login session to use, and those you only need a networked computer to use.
We've already mentioned that you can use a telnet program on your PC to log into the CIS Unix systems. This is a special case of a client program on your PC talking to a server program on the Unix system. (Specifically, your telnet client program talking to our telnet server.)
Generally, you can use other client programs on your PC to talk to our Unix servers for more specialized services. The primary protocols and their uses are:
FTP protocol for file transfer (in either direction) between the PC and the CIS Unix hosts;
POP or IMAP protocols for receiving e-mail on your PC from the CIS Unix hosts;
SMTP protocol for sending e-mail from your PC;
NNTP protocol for reading and posting Usenet news articles from your PC;
SMB or Appletalk protocols for accessing your Unix files from your Windows PC or Mac (respectively), using the same point-and-click methods by which you access files on your local disk.
HTTP and HTTPS protocols to communicate with our (respectively) unsecure and secure web servers.
In this section, we'll briefly discuss how to configure your client programs with the correct parameters to talk to our servers. We assume your network connection itself has been configured properly, but the details of doing that are beyond the scope of this document; contact your network service provider's support staff if you need help.
Also, given the wide variety of PC client software that's out there, we can't be too specific about the detailed methods for their configuration. Rest assured, however, there has to be some way to do it.
Usenet is the set of people who exchange electronic articles tagged with one or more universally-recognized labels, called “newsgroups.” Usenet is a world-wide system, but we also have “local” newsgroups for announcements and discussions relating to UNH (although these are currently very inactive). You can read these articles (or generate your own) by using the slrn newsreader.
There are about 3200 newsgroups available at UNH, covering issues from abortion to zines. Sorting out the ones you might be interested in pursuing is tricky.
Here is an official CIS policy statement with respect to Usenet:
![[Important]](http://pubpages.unh.edu/images/important.png) | |
Usenet newsgroups are based on open and free expression of all ideas and interests. That means you may find some material to be offensive. The University of New Hampshire and the Department of Computing and Information Services assume that anyone accessing Usenet understands this and takes responsibility for what they select to read, just as they would at a bookstore or newsstand or other medium. |
To transfer files between your PC and your CIS Unix account's home directory, you need to specify three things to your FTP client program:
your CIS Unix username;
your password;
a CIS Unix host name.
All CIS Unix hosts allow (non-anonymous) FTP client access. For
the host name, it's recommended you use cisunix.unh.edu; that will pick an
appropriate host at random. Specifying this information will allow you
to access your account; consult your FTP client software documentation
for specific methods of transferring files back and forth.
If you use Netscape, FTP transfers are relatively convenient and
intuitive: simply open the URL ftp://joe@cisunix.unh.edu
(remembering, of course, to substitute your own username for joe, and no trailing slash). You'll be asked to supply your password;
assuming you type it correctly, your CIS Unix home directory will then
be displayed in Netscape's window. You can drag-and-drop files from
your PC's desktop to transfer them to your Unix directory; shift-clicking on
a file in Netscape's window will transfer it to your PC.
Editor programs are used to create and modify text files on the system. You can get only a limited amount of work done on a Unix system without learning how to use an editor.
There are three major editors available on the system: vi, pico, and emacs.
vi is probably the most popular editor. It is usually available on all Unix systems from any vendor, so it's a good choice for those people who use a lot of different systems. It is moderately difficult to learn.
pico is a good choice for novice and occasional users. It displays a command menu at the bottom of the screen at all times, and has a built-in help feature.
emacs is probably the editor of choice among advanced users. It provides a powerful and rich working environment. You can read mail and Usenet news from inside emacs itself; you can do many file manipulation functions, even debug programs. It is also highly customizable; given some skill in LISP programming, you can make the editor do just about whatever you can think of.
You need to specify a news server to retrieve and post
Usenet news messages using news-client software.
For on-campus users, the news server is the
machine news.unh.edu.
Customers of a commercial internet service
provider will need to specify their provider's news server instead.
AT&T Broadband
customers in New Hampshire, for example, should specify
netnews.attbi.com.
This section discusses the different ways to get your files printed out on paper.
You can use the lpr command to print to printers in the Student Computing Clusters (SCC). You can either print text files, or PostScript files.
The syntax for the lpr command is:
lpr[-Pprintername]filename...
where
printername is either scc
(for black and white printing)
or clusters_color (for color printing),
and filename is
a list of one or more filenames you want printed, separated
with spaces. If you don't use a -P option,
the scc printer is used.
Jobs sent to the SCC printers initially go to a holding disk on the SCC servers. You can obtain your printout by using a copy card in the appropriate cluster. Copy cards can be purchased from the self service vending machines in any of the clusters. Your output will be printed once your card is debited.
Some examples: to get “quick and dirty”
of the text file poli.c:
%lpr -P scc poli.c
To print the PostScript file file.ps:
%lpr -P scc file.ps
You can use the a2ps command to get
“nice” listings. For example, to print the text file
poli.c:
%a2ps poli.c
a2ps has numerous options for adjusting the output; give the command
%man a2ps
for the complete story.
Adobe's “Portable Document Format” (PDF) is a popular method of distributing high-quality documents on the Internet. The Adobe Acrobat Reader software (acroread), which is installed on all our Unix systems, can be used to convert PDF files to PostScript for printing. Example usage:
%acroread -toPostScriptfile.pdf| lpr
This might work to print out a PDF file in color:
%acroread -toPostScriptcolorfile.pdf| lpr -P clusters_color
But I haven't tried that myself. Let me know if you do.
The Acrobat Reader documentation describes other options to the acroread command.
There are a number of `private' departmental printers accessible via lpr; please don't use them unless you are authorized.
Free ad: if you printing needs are intense, you might want to check out the UNH Printing Services website; you can upload files from your PC or Mac for printing.
If you have a “local” printer available to you (one that prints documents directly from your desktop machine) you might be able to use the lpansi command on the Unix login servers (Gauss, Zeno, or Euler) to print Unix text files. The command syntax is:
lpansifilename...
Your computer's communications software needs to support so-called “ANSI printing codes” in order for this to work; some do, some don't. Both QVT/Term and SSH Secure Shell work fine.
In addition, Pine has the option to set up an “attached-to-ansi” printer; if ANSI printing works for you, you can use this option to print messages from within Pine.
You can conveniently access your CIS Unix home directory and files from remote Windows, Linux, and Macintosh systems on the network. Your Unix home directory can appear on your computer's desktop as a normal folder; you can use your usual point-and-click methods to access and manipulate your Unix files. In addition, you get access from Student Computing Centers machines when you log in there. This access made possible by the “Samba” package, which runs on the CIS Unix login servers (currently Euler, Zeno, and Gauss).
A couple caveats:
![[Note]](http://pubpages.unh.edu/images/note.png) | Off-campus Use |
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Samba service is not available to unauthorized off-campus computers. In order to access Samba from off campus you will need to set up the UNH VPN first. |
| Password |
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In some rare cases, you may need to change your password in order to use the Samba service. For almost all users, changing their Blackboard password will work. See Section 6.3, “Activating Your Account” for information on changing your password. |
Although we can't cover every possible mode of Samba usage, we'll provide some brief guidelines for each major type of client For more information on Samba, see the Samba website.
All modern (and even not-so-modern) versions of Windows have been able to access Samba clients. Unfortunately, different versions of Windows differ in their method. The following steps seem to work well in Windows XP and Vista:
Choose from the button in the Windows task bar.
In the resulting dialog box, specify
\\cisunix.unh.edu\homes
for the item to open, and click .
You should get a dialog box asking for your username and password; type in your CIS Unix username and your CIS Unix password.
All modern versions of the Macintosh OS have been able to access Samba clients. Here's what we do:
Activate the MacOS Finder.
Either type Command+K or choose from the menu.
In the resulting dialog box, specify
smb://cisunix.unh.edu/homes
for the address to open, and click .
You should get a dialog box asking for your username and password; type in your CIS Unix username and your CIS Unix password.
Linux offers a number of options for connecting to a Samba server. Here's a method using a recent version of GNOME on a Fedora linux host:
Choose from the menu in the top menu bar.
In the resulting dialog box, choose "Windows Share" from the "Service
Type:" pulldown menu;
type cisunix.unh.edu for the "Server:";
type homes for "Share:";
type your username for "User Name:";
and click .
You should get a dialog box asking for your domain and password; ignore Domain and type in your CIS Unix password.
Alternatively, you can use command-line based access:
Use the su command to get root privilege.
If necessary, create an empty directory to use as a mount point:
#mkdir cisunix
Give the mount.cifs command:
#mount.cifs //cisunix.unh.edu/homes cisunix -o user=username,uid=uid
… where you replace username
and uid with the username and UID
number you use on your Linux box. (You can give the
id command to find out what your UID is.)
You'll be asked for a password; enter your CIS Unix password.
A brief overview of some other packages available on the CIS Unix systems:
Programming. Unix was designed by programmers, and, as a result, it's a very powerful system for writing programs.
All systems allow you to program in just about any computer language you like, including C, C++, Gauss, Fortran, Java, Tcl, Python, Ruby, and Perl. Lots of supporting libraries and utilities are installed.
The GNU debugger gdb debugger is available on all systems.
Text Formatting. There are two major packages available for high-quality text formatting on all systems: groff and teTeX. The teTeX package includes Donald Knuth's TeX software, Leslie Lamport's LaTeX2e software, and a panoply of supporting software.
Mathematics and Statistics. All systems provide the LAPACK and BLAS libraries for linear algebra.
Plotting. The gnuplot program is available on the systems; it is an interactive program for 2-D and 3-D plotting of functions and data. The program can display its plots on graphics-capable workstations and terminals; it can also produce PostScript files for printing, and PNG files for web pages.
Speling Chekers. The systems offer three spell-checking programs, spell, ispell, and aspell. The recommended ispell program is interactive, shows the context of possible spelling mistakes, allows user-specified corrections, and has built-in help.
You may accidentally delete or damage one of your important data files on the Unix systems. Fortunately, it's possible in many cases to get it back.
The file servers on which user files reside take “snapshots” every so often of all the files on their disks; these snapshots remain on disk for up to two days. The snap_restore command provides a convenient way to restore your deleted file (or revert to a previous version of a mangled file) on your own. See the snap_restore web page for more information.
If you waited too long to try to restore the file and it disappeared from the file server snapshots, you are still not out of luck: user areas on disk are backed up daily to tape, and you can request that it be restored from the tape backups.
The backups are typically performed around 3am every evening. For efficiency, most backups are incremental; only those files changed at some point since a previous backup are stored on tape. A full backup is made every week.
If your lost file existed on disk during any backup (full or incremental) it will probably have been captured on tape. To restore it we need the following information:
the pathname of the file: its name, and where it was in your directory;
the date it was deleted;
the date the file was last modified (before deletion). (Note that any changes you made to the file on the day of deletion will almost certainly be lost.)
You may not know this some information precisely; that's OK, but please supply as good an estimate as you possibly can. Enter this information on the CIS Help Desk Questions form. Every attempt will be made to restore your file by the next working day. You will get a reply by e-mail telling you what happened in any case.
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| 10. Using The Web |  | 12. Additional Unix Information Sources |