- Welcome from the Chair
- Ohio State ECE At-A-Glance
- Contact Us
- Visit Us
- 5-year Strategic Plan
- Industrial Advisory Board
- ECE Outreach Program
- Administrative & Student Resources (internal)
- Job Openings in the Department
- Computer and IT Resources
- AV: The DL260 AV System
- AV: BenQ MP620p Manual
- MSDNAA: Download Information
- Unix: Running Background Jobs
- Unix: Useful UNIX Commands
- Windows: The ER4 PC Labs
- Windows: Restoring Files
The projector was professionally installed and configured. Please do not attempt to "correct" anything within its configuration menus. If you believe that someone else may have "corrected" something incorrectly, please contact the Site staff at email@example.com.
The Remote Control
The remote control has its own power switch located along the right side, near the top of the remote. It is labeled "R/C ON OFF" Make sure the remote is powered on before you try to use it and please remember power it off when you are done.
To turn on the projector, select the "Power" button. When the projector is off, there is an amber light on the side of it facing the floor. When it is first turned on, this light will start flashing green... this means that the projector is on, but that it is warming up. When the projector is done warming up, this will be a solid green light... you'll also be able to see the picture projecting onto the screen at the front of the room.
|Buttons of note:
The podium contains a PC. Anyone with an ECE username and password can log into this system. There are no guest accounts. The PC has full network access and is loaded with a standard software set. It also has a CDROM drive, and a USB connection connected to the podium's connection panel.
The podium has a connection panel on its left side (as you face the podium from the PC user's position). From left to right, it's connectors are:
- Video - Yellow video input with left and right audio jacks. Corresponds to the "Video" button on the projector's remote control.
- S-Video - S-Video input with left and right audio jacks. Corresponds to the "S-Video" button on the projector's remote control.
- Component - Y, Pr and Pb inputs with left and right audio jacks. Corresponds to the "BNC" button on the projector's remote control.
- Laptop - SVGA video input. Corresponds to the "Comp" button on the projector's remote control. See note about switching between the Podium PC and Laptop video feed which share this input on the projector.
- Network - a live network connection, available for laptops or other network capable devices.
- USB - this USB connection ties back to the PC contained within the podium.
Please note that the podium PC and the laptop connector share the same source input on the projector. To switch between the two, there is a switch box inside the podium. If you open the left door, at the very top of the opened space is a switch box. Button 1 corresponds to the PC. Button 2 corresponds to the laptop.
Connecting a laptop to the projector will vary by laptop type. Different hardware types will vary as may operating systems.
What all systems will have in common:
- Your video output port on the laptop must be connected to the SVGA/"Laptop" connection port on the podium's connection panel. If your laptop uses a "standard" SVGA cable, one can be found inside the podium, if you do not have your own.
Everything else may differ and the laptop owner will need to know how their system works. If you are helping someone debug their laptop's video connection, here are a few things that might help:
- Macintosh laptops often require an adapter to work with the SVGA connector in the podium. Said adapter is the responsibility of the macintosh owner (the site staff just doesn't have one).
- Some laptops will require that a key combination be pressed such that the video signal goes to the external video port as well as (or instead of) the laptop's own screen.
- If that key combination cannot be found, some laptops will automatically select the external video port when they are rebooted with the video cable already connected to the laptop and the projector.
- When all else fails, refer to the laptops owners manual, or use the podium's PC to access the laptop vendor's web site for documentation.
This document covers these subjects
- Policies on background jobs
- Foreground vs. background jobs
- Output and input for background jobs
- Redirecting input and output
- Unattended background jobs
- Running multiple unattended background jobs is not allowed
- Commands for manipulating jobs
Policies on background jobs
- If you are actually sitting at a machine, there are no limits on the number of background jobs you may have on that machine.
- You are limited to one unattended background job, on one machine, at a time.
- That job must be `nice'd (that is, it must be set to run at a low priority) to minimize the impact on other users of the machine.
- Locking the screen and leaving the machine is not an acceptable way of running unattended jobs.
- If you violate these rules, your background jobs will be killed and you may lose your computing privileges.
Foreground vs. background jobs
If you don't want to wait for a command to finish before you see the prompt again, you can run the command in the background. Any shell command can be run in the background by typing an ampersand (&) at the end of the command line. The following command:
- wc /hp-ux &
will count the number of bytes in the UNIX kernel, and it will take a second or two to complete. Try it with and without the ampersand and notice how the shell doesn't wait for the command to complete when you execute it in the background. When you start a background job, you'll get a message that looks like this:
-  8397
The number in brackets is a `job number' assigned by the shell to the background job, and the second number is a `process number' assigned by the operating system. When a background job is completed, you'll get a notice from the shell that looks like this:
-  Done wc /hp-ux
Output and input for background jobs
When background jobs require input from the keyboard, they stop running. You must bring them into the foreground in order to supply them with input from the keyboard.
Because of this, it is usually a good idea to redirect the input and output of background jobs.
Redirecting input and output
Output redirection can be used for any command, not just background commands. For instance, the command
- ls -R ~ >listing
will do a directory listing of your home directory and all of its subdirectories and save the output in a file called listing. You do not need to create the output file in advance---it will be created if it does not already exist. Caution! When you redirect output to an existing file, that file is overwritten. The previous contents will be lost. If you wish to append the output of a command to a file, use the redirection operator >> instead of >. To use input redirection, you must first create the file and put some appropriate input into it. You can do this with an editor such as emacs or vi. For instance, if the file testrun contains a series of Matlab commands, then the command
- matlab <testrun >testrun.out
will cause Matlab to take its commands from the file testrun and to put the results in the file testrun.out.
Unattended background jobs
However, it is a rule of this computing site that unattended jobs must be nice'd. This means that they run at a lower priority. The jobs will still run to completion, but they will not interfere with other people using the machine. For example,
- nohup nice matlab < inputfile > outputfile &
will run Matlab in the background at a lower priority (with input and output redirected to files). csh and tcsh have a built in nice command that follows the syntax listed above. If you are using a different shell, or if you are explicitly invoking /bin/nice, see the man page for the correct syntax.
If you forget to nice a background job when you start, or if the job takes longer than you anticipated and you decide to log out and go to lunch, you can use the command
renice -n 19 to lower the priority of already-running jobs. The argument to the renice command is a process number (the second of the two numbers reported when you started the job.) For example, the command:
- renice -n 19 8397
will lower the priority for the job whose process number is 8397.
If you've forgotten the process number, you can use the command
- jobs -l
to list all of your jobs and their process numbers. Note: the jobs command only knows about jobs started from the same window. See the manual page for the ps command to learn how to find out about jobs started from a different window.
Running multiple unattended background jobs is not allowed
To run your commands one at a time, create a file containing a list of the commands you want to run. This is called a `shell script'. Then you can run the shell script, and each of the commands in it will be executed in turn. You run a shell script by typing its file name at the shell prompt (don't forget the & if you want it to run in the background and nice if you plan to leave before it finishes.) You may need to set execute permission on the file so that the script is runnable---use the chmod command, like this:
- chmod u+x filename
Commands for manipulating jobs
- The shell provides a number of commands for manipulating background jobs:
||(Press Z while holding down the Ctrl key.) Suspends the current foreground job. You can type this any time and you'll get a shell prompt. You can then put the current job into the background with the bg command or resume running it in the foreground with the fg command.|
||Lists current background jobs in the current window.|
||Brings a background job to the foreground.|
||Restarts a stopped or suspended background job.|
||Stops a background job. This doesn't kill the job, but it will not continue executing until it is restarted.|
||Terminates a background job.|
||Waits for all background jobs to terminate.|
||Runs jobs at lower priority.|
- Consult the csh manual page for more details on how to use these commands. The renice and ps commands have their own manual pages.
This document covers these subjects
- Changing your password
- File manipulation commands
- Directory commands
- Document preparation
- On-line manual pages
- Miscellaneous commands
Changing your password
- Change your password. Do this regularly, and keep your password secret.
File manipulation commands
cp file1 file2
- Copies file1 to file2.
mv file1 file2
- Moves file1 to file2. If the arguments are in same directory, this command just renames file1 to file2. If file2 is a directory, file1 is moved to that directory
- Removes filename.
cat file1 file2
- Concatenates file1 and file2 and prints the result to the screen.
cat file1 file2 > file3
- Concatenates file1 and file2 and puts the result into file3.
- Prints file1 to the screen, but pauses when the screen is full.
- Another paginator, similar to more.
- Sends file1 to a printer.
- Cancel a printer request. You must use the job identification reported by the lp command when you ran it.
- Show the print queues. You can use this to show how many print requests are ahead of (or behind) yours in the queue. lpq will also report request ids, if you forget them.
- List the contents of the current directory.
- List contents of the directory dirname.
- List all the files in a directory, including ones whose names begin with a period (.)
- Long listing. List the contents of a directory, with the protection, owner, size, modification date, and name of the files.
- Long listing. Synonym for ls -l.
- Print working directory. Prints the name of the current directory.
- Change directory. Changes the current directory to dirname.
- Change to parent directory. Moves up one level in the directory hierarchy.
- cd with no arguments will change the current directory to the home directory.
- ~ is shorthand for the home directory, so cd ~ will change the current directory to the home directory.
- ~username is shorthand for username's home directory, so cd ~username will change the current directory to that user's home directory.
- Make directory. Creates a new, empty directory named dirname.
- Remove directory. A directory must be empty before it can be removed.
- Disk usage. Summarizes the space taken up by all the files in a directory and its subdirectories.
- Report information about your disk quota.
- Emacs editor.
- vi editor.
- Invokes the LaTeX typesetting program.
- dvips converts the output of LaTeX to postscript for the printers. The output is automatically sent to the printers unless the -o option is used.
- Spelling checker.
- Drawing program.
- DVI previewer. Displays a DVI file produced by LaTeX on the screen. You can use previewers to check how a document looks without wasting paper to print it.
- Postscript previewer. Displays a postscript file on the screen. Another good way to save paper.
- c compiler.
- c++ compiler (GNU).
- Fortran compiler.
- Pascal compiler.
- Utility for building and maintaining large programs.
Online manual pages
- Bring up the on-line manual page for a command.
- Bring up the on-line manual page for the man command.
man -k keyword
- Searches all the manual pages for ones relevant to the keyword.
- Shows current date and time.
- Shows other users logged into a system.
- Shows other users logged into a system, and what they are doing.
grep pattern filename
- Searches files for lines containing pattern.
- Exits an xterm window. If you are logged in remotely, this command will log you out of the system.
- Logging In
- Changing Passwords
- Logging Out
- File Storage
- Usage Policies & Guidelines
The first thing you need to know is how to log in. Press
Ctrl-Alt-Del. This means to hit and hold the Control key, then press and hold the Alt key, and then press the Delete key (and then release all three keys). This will pop up a window asking for your username and password and into which system you wish to log in.
USERNAME: Your username is the same as it is on the Unix and Email systems. By default it is your last name followed by your first initial. ECE usernames are limited to 8 characters in length. So, if your last name is more than 7 characters long, your username should be the first 7 characters of your last name followed by your first initial. In some cases, a last name is very common (at the time of this writing, there were 22 persons with the last name "Lee" on these systems), and then there may be more than one person who would have the same username. At this point convention is broken, as everyone must have a unique username. Please see the lab consultants in either DL557 or CL260 if you think your username is non-standard.
PASSWORD: Your default password is the string "EE" followed by the last four digits of your EMPLID number followed by your first and last initial. Note that the passwords are now synced between the PCs and Red Hat systems, but not the Mail server.
SYSTEM: The Windows machine may offer you more than one system to "Log on to". You always want to log into the
ECE domain. Logging into another domain will not be possible, and even if you can do so, logging into the local machine will limit your network capabilities.
Ctrl-Alt-Del to bring up the Windows Security Menu. A new window will appear with several options, including logging out and changing your password. Your old windows will be hidden, but have not been destroyed.
Change Password...". You will now be prompted for your current password and your new password. You will also have a confirmation box where you must type in the new password a second time (this is to decrease the possibility of typing errors). Hit the
OK button to have the new password take effect.
There are many ways to do this, but the following is the recommended method within ER4.
- Close all of your running processes.
- Bring up the Windows Security Window by pressing
- Select the
"OK"in the pop-up confirmation window.
- Turn off the monitor (NOT the CPU), straighten the area around your computer, and push in your chair as you leave.
SERVER STORAGE: Every account on the ER4 PCs has a 2.0GB home directory. This is the same space as is each student's home directory on the Unix systems. It is mapped to the PC as the Z drive and should be used for all file storage. NOTE BENE: Files saved in the temp space of the C Drive of the local Windows system are not saved to your home directory. Such files may be lost between login sessions and in fact probably will be... use the Z drive for all file storage.
LOCAL CLIENT DISKS: Some of the software on the systems requires that the local client disks be writable. These disks are only to be used by the software's internal processes that require that access. Student files saved to the client disks violate site policy and may be deleted without warning. Note also that cloning software is regularly run against these machine and will wipe out user data without SysAdmin intervention. Data lost from the client machines is irretrievable.
CDRW Drives: Each ER4 PC has an internal CDRW drive. These are the intended method for long term file storage. It is highly recommended that all students make use of these drives for personal backups.
XILINX: Xilinx is a programmable logic software package used in ECE261 and ECE561, it will likely be your first PC oriented software package whose use is required by your classwork. A student version of Xilinx also comes with the textbook require for those two classes.
MATLAB: Matlab is available on the ER4 Windows Systems. It is a fully functional system and can be used for all class projects. However, Matlab jobs submitted to a Windows system require the user to be with the PC for the duration of the job. Some Matlab jobs can take a long time to run. Those jobs are better submitted to the ER4 Unix systems which allow for untended, back ground processes.
MICROSOFT OFFICE: As a part of the University-Microsoft agreepemtn, MS Office is available on all of the ER4 PCs. A "full" installation was made, but this does not necessarily include every extension or template for each given package. If you find need of something that has not been installed, please send a request to site.
All usage policies that apply to the Unix labs also apply to the PC labs. Thus no eating or drinking anything other than water in secured containers, is allowed in the labs, and the machines are only to be used for ECE classwork, etcetera...
SYSTEM MODIFICATIONS: Any modifications to the system, be it through modification to the registry or to system files is absolutely forbidden. The systems are set up to run as multi-user workstations and as such are not to be modified by individuals. If you feel that a system modification is required for your scholastic works, please send email to site, and we will take it under advisement.
MULTIPLE PROCESSES: Unlike the HPs, there are no remote users on the ER4 PC systems. Thus, there are no limits on the number of processes that you run (limited to one machine). However, please note that resources on any machine are finite, and the more you run, the slower any given single task will be performed. For best performance from the PCs, please only run what you have to.
SCREEN LOCKS: Please lock your terminal if you are stepping away from it. To do so, bring up the Windows Security Window (by pressing
Ctrl-Alt-Del) and select
Lock Computer. Note that PCs are only to be locked for short periods of time... don't exceed 10 minutes or you may be logged off.
PRINTING: the same printing policies apply to the ER4 PCs as to the Unix systems. The quota system is common between the two systems. Using the printer in the PC lab will count against your Unix quota and vice-versa.
FILE STORAGE: all users have 2.0GB of storage space in their home accounts. This storage is deemed sufficient for student academic purposes. It can be reached as the Z drive. Note: for most users (you should know if you are an exception), your ER4 Windows Desktop, My Documents, and Application Data folders are all redirected into folders of those same names on your Z drive. So files saved on your desktop, count against your quote.
SOFTWARE INSTALLATIONS: users are not to install any software on the ER4 systems. This includes installing software in your home directories (Z drive) so that they can be run on the system. This most specifically includes networked programs like chat, file sharing, and instant messaging systems. Violators of this policy will loose account privileges. Requests for software related to academic pursuits should be made to the Site staff.
GAMES, CHAT & INSTANT MESSAGING: The ER4 PCs are to be used for school work only. Any extraneous use should be restricted to off-peak times, and should be restricted to programs installed by the systems administrators (see above). If asked by a staff member, or even by another student, non-class related work should be suspended immediately.
FILE SHARING: the installation and/or use of file sharing software including but not limited to those of the P2P type (ie: Kaza, EDonkey, etc) are explicit violations of University and Departmental policy (both in the student labs and on University Networks in general). Violations may result in loss of account and network-access privileges.
REBOOTING: Sometimes PCs have to be rebooted. It's just the nature of these systems. However, such reboots should only be performed by ER4 staff. If you feel your PC needs to be rebooted, please see the student consultant in CL260. Please do not reboot it yourself.
File restoration with ER4 is now handled exclusively through the Windows systems. To utilize this ability, go to your Z drive, and find the folder that contains (or contained) the file or folder you are seeking. Right click and select "Properties". Here you will find a tab that says "Previsous Versions".
Find the "Time" that the corresponds to the version of the folder you are interested in restoring. Highlight this line and select your action:
- View: This allows you to see the content of a folder. You can drag and drop from this view.
- Copy: This lets you designate a location to which the folder will be copied.
- Restore: This restores the folder to its previous location. NOTE BENE: this will over write current content. We generally recommend that you use one of the other two options.