Introduction to Instructional Computing at UCB

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Introduction to Instructional Computing at UCB

• How to avoid the wrath of root
• Or how I learned to stop worrying and love the
  command line

Presented by the CSUA http//csua.berkeley.edu
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About this presentation

• Quick overview of the basics
• Some things you will know, some things you will
  not know.
• Slides will be posted on the CSUA website
• Divided into two sections
• Part 1 Instructional resources
• Part 2 Basic basic basic UNIX

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Dont be embarrassed...

• You are not expected to know any of this
  information coming into Berkeley, but any CS
  class you take will depend on it
• Dont be afraid to ask questions
• You can ask in private
• CSUA Office 343 Soda
• HKN UPE Office 345 Soda

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Part 1

• Instructional resources

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What is Instructional Computing

• Collection of servers, labs, and resources to
  help you do your work
• If in doubt, you can visit http//inst.eecs.berkel
  ey.edu and find the answer to almost everything!

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Where are the computers?

• Instructional labs that are open to everyone
  (need a card key after 630pm and weekends)
• UNIX 271 Soda, 273 Soda, 275 Soda, 277 Soda
• Windows 330 Soda
• Windows passwords are not in sync with UNIX
  passwords, you must use your default password
  from your form to login
• Mac OSX 199 Cory
• http//inst.eecs.berkeley.edu/clients
• Other labs are reserved for specific courses
• Printers are in or near each of these labs
• Class accounts have a printing quota

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Some rules for the labs...

• No food or drink in the labs
• Be courteous to your fellow students
• Do not unplug anything
• Dont be a hoser
• No games, chat, etc during peak usage times
• Read your account form!

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Arent there labs with(lower-case-w) windows?

• The CSUA lounge has windows, radiation-ball-produc
  ed lighting, couches, and computers. And you can
  eat and buy cheap snacks in the CSUA office next
  door!
• Location 337 Soda
• Login as user xterm, password xterm, then
  choose the instructional server youd like to
  login to and use your class account login.

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Be not afraid...

• Dont be afraid of the console
• There is more to life than the mouse
• Like it or hate it, youll have to learn it
• There are a lot of resources to help you
• You cant destroy the computers, just your own
  work

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Working from home

• You must use a secure transport to connect to
  Berkeley
• Remote console/text access
• SSH (Secure Shell) A secure equivalent of
  telnet
• Remote file access
• SCP (Secure Copy) A secure equivalent of remote
  copy
• SFTP (Secure FTP) A secure equivalent of,
  surprise, FTP!
• Remote graphical access
• X/Windows run applications on the server and
  export the display, directly analogous to the
  console paradigm above
• Popular versions of the above class of software
  are available at http//software.berkeley.edu

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SSH

• This will be the primary way you connect to
  Berkeley. It will dump you out at a command line
  on the remote server.
• The version _at_ software.berkeley.edu has
  integrated file transfer and is easy to use
• Demo
• Some people find the above tool to be unstable
  and/or generally prefer Putty
  (www.chiark.greenend.org.uk/sgtatham/putty)

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Login Servers

• Popular login/project servers
• pentagon.cs.berkeley.edu (Solaris/Intel)
• po.eecs.berkeley.edu (Solaris/Intel)
• rhombus.cs.berkeley.edu (Solaris/Intel)
• nova.cs.berkeley.edu (Solaris/Sparc)
• star.cs.berkeley.edu (Solaris/Sparc)
• solar.cs.berkeley.edu (Solaris/Sparc)
• http//inst.eecs.berkeley.edu/clients

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Remote X/Windows

• This gives you a graphical shell and allows you
  to run windowed applications
• The apps run on the server only the UI is
  exported to you
• If you can avoid using it, do so
• Its big, its slow, and its a resource hog
  (both for you and the network)
• But sometimes you absolutely have to...
• Exceed is the tool that UCB provides

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Working from home

• More software (mostly class-specific) at
  http//inst.eecs.berkeley.edu/instcd
• Emacs, STk, perl, putty, cygwin, etc.
• Check with your TA to ensure that the
  class-specific files are up-to-date for your class

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Transferring files

• Your computer lt-gt Berkeley
• SSH Secure Shell use the integrated client
• Putty pscp.exe
• Server lt-gt Server
• scp ltsourcegt ltdestinationgt
• source/dest of form login_at_serverfile (or dir)
• e.g. scp myfile cs200-xx_at_po.eecs.berkeley.edusrcf
  iles
• Also sftp an interactive shell like FTP

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Email

• Checking on the server, while connected...
• pine, mutt, etc.
• Forwarding elsewhere...
• Put the email address you want to forward to into
  a .forward file in your home directory

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Email

• From an email client off campus
• Uses IMAP rather than POP3
• Your email client must support SSL (port 563)
• Server imail.eecs.berkeley.edu
• http//inst.eecs.berkeley.edu/share/b/pub/email.he
  lp
• From the intarweb
• http//imail.eecs.berkeley.edu

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Newsgroups

• From any on-campus computer (including the dorms)
• Set your news/nntp server to news.berkeley.edu
• From off campus
• Server authnews.berkeley.edu
• Requires SSL (port 563), no SPA
• Use your Calnet ID for authentication

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Newsgroups

• On teh intarweb
• http//inst.eecs.berkeley.edu/webnews
• Use your instructional login

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Web pages

• If your class requires a web page all you need to
  do is to create a directory called public_html in
  your home directory
• chmod 711 (drwxx--x) to make it world viewable
• You can access your new site in the form of...
• http//inst.eecs.berkeley.edu/username/
• Cannot use tools that publish to the web
• Class accounts are not for personal pages
• They also get wiped after each semester

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Disk space

• Check quota regularly!
• You can only be over soft for 7 days
• Once you hit hard you must clean up
• Things that tend to fill your quota fast
• core files
• Media and archives (.zip, .mp3, .avi, etc)
• inst will be very unhappy to find these...
• Intermediate compiler files (.o, etc)
• Disgruntled root

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Disk space

• If you are over quota
• You will have problems writing files
• You may have problems logging in
• If you cant login or write because of quota
• Delete files!
• SSH or SFTP in and delete files
• Use FAILSAFE on instructional machines for
  login type and delete files (on Sunrays)

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More disk space... really...

• There is a land called /home/tmp
• Medium-term storage, not for hosing
• Use mkhometmpdir to create a space writable by
  you
• Can only be done once per account
• Instructional monitors this directory for hozers

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Logout!

• Please remember to log out of a computer you are
  done with
• Sunrays Right click on the desktop
• Windows Start ? Shut Down ? Logout
• MacOSX Apple ? Logoff
• Console exit
• TIP Dont leave until you see the login screen!

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Windows accounts

• Do not store your data on your desktop!
• Do not store your data in My Documents!
• Use your home directory
• Anybody taking EECS courses can get a windows
  account. Just run newacct.

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Getting help (in this order)

• RTFM (Read The Fantastic Manual)
• man is your friend
• apropos is not just a French word
• Google knows all, and then some
• Read insts help repository at http//inst.eecs.be
  rkeley.edu
• Ask the person next to you
• Drop by the root cave (666 2 Soda)
• Inst_at_eecs.berkeley.edu, NOT root!!!
• Come talk to us in 343 Soda! )

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If something seems wrong ...

• inst_at_eecs.berkeley.edu is the support email for
  the instructional environment. Make sure you
  include the following
• Your login, computer, and lab
• What you were doing and what the error is
• What instructions you were trying to follow
• Has it ever worked before?
• And for problems from home, add the following
• What operating system you are using
• How the computer is connected to the Internet

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Part 2

• Basic basic basic UNIX

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Some notes

• UNIX doesnt always make sense at first
• UNIX programmers hate vowels
• UNIX is CaSe SeNsItIvE

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Getting Help

• man MANual page (called man pages)
• Exstar gt man mkdir
• Exstar gt man man
• apropos With regard to searches commands
• Exstar gt apropos directory

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Moving around

• pwd Tells you your current directory
• Exstar gt pwd/home/cc/cs61a/su05/class/cs61a-x
  x
• cd Change Directory
• Exstar gt cd project1

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Moving around

• ls LiSts the files in the directory
• Exstar gt lscore_at_ lab1 plural.scmdupls.scm pi
  gl.scm sumofsquares.scm
• Exstar gt ls lab1part1.scm part2.scm

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Directory management

• mkdir Creates (MaKes) a directory
• Exstar gt mkdir homework2
• rmdir Deletes (ReMoves) a directory
• The directory must be empty!
• Exstar gt rmdir homework2
• If you want to delete an entire directory tree...
• star gt rm rf homework2
• THIS IS A DANGEROUS COMMAND!!!!!

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Files

• touch creates an empty file
• Exstar gt touch lab1.scm
• rm ReMoves a file
• Exstar gt rm lab1.scm

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Files

• mv MoVes a file
• Also used to rename files
• Ex (move)star gt mv part1.scm lab1dir
• Ex (rename)star gt mv part1.scm
  oldbrokencode.scm
• cp CoPies a file
• Exstar gt cp part1.scm part1old.scm

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Printing

• lpr Line Printer (prints a text file)
• Find the printer name on the printer or on the
  inst website
• Exstar gt lpr P printer source.scm
• enscript Converts a text file to a PS file
• Our printers can print PS directly, with LPR
• This tool allows you to change the font, print
  multiple pages per page, and control the output
  in more detail
• See the man page for details

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Printing

• Be courteous manage your print jobs
• Determine what is already on the queue
• Ex star gt lpq Plw274
• Cancel all your jobs
• Ex star gt lprm a all

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Editing Files

• vi VIsual Editor
• Exstar gt vi file
• Exstar gt man vi
• emacs The Beast, a powerful OSHHEditor
• Exstar gt emacs directory
• Both can be difficult to learn. The CSUA will
  host a complete info session on emacs Thursday!
  Other resources...
• http//www.math.utah.edu/djohnson/reference/Emacs
  Refcard.pdf
• http//www.csua.berkeley.edu/jrleek/emacs-basic.p
  pt
• http//www.eng.hawaii.edu/Tutor/vi.html

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File permissions

• There are 3 kinds of people in this world
• You (user)
• Your friends (group)
• Everybody else (other)
• Each type of person is given (or denied)
  permissions to
• read
• write
• execute

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File permissions

• Having execute permission for a file means that
  you can run that program
• Having execute permission on a directory means
  that you can cd into it
• Having read permission on a directory means
  that you can list the contents

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File permissions

• Changing the permissions
• star gt chmod ltpermsgt ltfile or directorygt
• User Group Otherrwx rwx rwx rwxrwxrwx42142142
  1rwxr-x--x 751

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Login and user information

• chfn Changes your profile information (allows
  you to have your real name displayed when people
  look who is online, essential for group work)
• Expo gt chfn
• finger Look up information on a user
• Exstar gt finger cs61a-xx
• who See who is online
• Exstar gt who
• A similar command is just w

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UNIX on Windows!

• There are several tools to bring the power of the
  UNIX environment to your Windows system. Cygwin
  is probably the best of them.
• http//www.cygwin.com
• Includes practically every UNIX tool and app
  available compilers, databases, web servers,
  etc!
• Also includes a complete X/Server that you can
  use to connect graphically to campus
• You cannot avoid becoming an expert on UNIX in
  your time here and Cygwin will help you master
  UNIX!

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Remote source editing

• For those of you in 61b, 61c, or upperdiv, JEdit
  is a powerful IDE for source editing and allows
  you to edit files over the network (using SFTP as
  a transport)
• Most class projects require library-access that
  you cant get at home, so you need to work with
  the code on the server
• Editing in the console gets old FAST!
• http//www.jedit.org
• Also install (from within the program) the FTP
  package

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Questions?

• Brought to you by the...
• Computer Science Undergraduate Association
• Sign up and become a member, its free and there
  are a ton of benefits! Check out our site!
• http//csua.berkeley.edu
• Office 343 Soda Hall