Orientation for fresh VDTT Students Introduction to UNIX

1
Orientation for fresh VDTT StudentsIntroduction
to UNIX

• July 28, 2001

Anup Gangwar
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Overview

• Prerequisites and goals of this course
• Differences between UNIX and Windows
• Overview of unices
• Basic UNIX commands and utilities
• Lunch Break
• File editors in UNIX
• Programming and Shell Scripting
• Document formatting using UNIX
• References and further study
• Thank You

3
Prerequisites and Goals

• What you should know
• Basic familiarity with computers
• Working Knowledge of atleast one operating system
• A will to learn
• What you will know
• This is not a complete UNIX tutorial
• Dont try to learn the whole UNIX in one day
• How to do the most common set of tasks with UNIX
• Self-Help is the best help
• Pointers for further information

4
Differences UNIX and Windows

• The UNIX and Windows philosophies
• Client-Server model of Computation
• Multi-User and Multi-Tasking. Login?
• Concept of the Kernel and User Shell
• Concept of file ownership and groups
• GUI on UNIX and X windows
• Tips
• UNIX is the most used OS in scientific and
  industrial community
• Instead of avoiding UNIX take it heads on
• Learning UNIX now will help you save precious
  time later on

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Overview of Unices-1

• The ?original? UNIX
• The ATT SVR and BSD
• Others HP-UX, Solaris, Linux, AIX, IRIX etc.
• Why are there so many unices? Vendor Wars!
• How do I understand all of them? POSIX!
• Tips
• Learn the common set of commands for all the
  unices
• Linux utilities will contain enhancements not
  found in others
• Try to clear trivial doubts like command syntax
  yourself

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Overview of Unices-2

• HP-UX
• Processors HP PA-RISC and Intel Itanium
• Vendors HP
• Markets High End Servers and Workstations
• Solaris/SunOS
• Processors Sun Ultra Sparc
• Vendors Sun Microsystems
• Markets All ranges of Servers and Workstations

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Overview of Unices-3

• Linux/GNU Systems
• Processors Intel 386 and up, Sun Ultra Sparc,
  IBM PowerPC etc.
• Vendors Free/GNU GPL
• Markets Low End Servers and Workstations
• AIX (Advanced UNIX)
• Processors IBM Power PC
• Vendors IBM
• Markets All ranges of Servers and Workstations

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Overview of Unices-4

• IRIX
• Processors MIPS
• Vendors SGI (Silicon Graphics International)
• Markets High End Graphics Servers and
  Workstations
• Others
• BeOS, FreeBSD etc.
• RTOSs PSoS, QNX, RTEMS, ?RTLinux? etc.

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What we have

• Philips VLSI Design Lab
• HP Server running HP-UX
• Sun Workstation
• Linux Workstations
• VDTT Lab
• Linux Workstations
• Windows NT Workstations
• New VLSI Lab
• Sun Workstations
• Windows NT Workstations

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Basic UNIX Commands and Utilities-1

• Files and Directories
• File Types Windows and UNIX
• File and Directory creation (Editors, mkdir, ln
  etc.)
• Listing contents of a directory (ls)
• File and Directory deletion (rmdir, rm etc.)
• File and Directory permissions (chmod)
• File and Directory ownership (chown, chgrp)
• Organizing your work in directories (mv)
• Tips
• UNIX doesnt have a recycle bin!
• Try not to make the mistake of rm -rf command

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Basic UNIX Commands and Utilities-2

• Managing your account
• What is meant by managing your account?
• Concept of setup files
• Why are there so many different Shells?
• Environment variables
• .bashrc and .cshrc files
• Customizing your environment with .bashrc and
  .cshrc files
• Example The TERM environment variable and stty
• Tips
• Try an environment variable on command-line first
• Always set the PATH variable properly

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Basic UNIX Commands and Utilities-3

• Remote process execution
• Why do we need remote process execution?
• Telnet and rlogin
• Remote execution of graphics programs
• X-Security, granting permissions and colormap
• The DISPLAY environment variable
• dot-rhosts (.rhosts), xon
• Moving files between computers FTP (?anonymous?
  FTP login)
• Tips
• Graphics performance suffers in remote graphics
  execution
• xhost is the worst thing to do!
• Ncftp is a better ftp client than the vanilla
  default UNIX ftp

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Basic UNIX Commands and Utilities-4

• Taking printouts
• Concept of network and local printers
• Printer languages Postscript and PCL
• GhostView and Acroread programs
• Spooling, Deleting and Checking a printer job
• Duplex printing and mpage
• Taking backups
• Tarring, zipping, gzipping and compressing
• Comparison with winzip and common filename
  extensions
• Tips
• Do not issue the command tar -cvf ltfile-namegt
• Acroread just might be a better program to open
  pdf files

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Basic UNIX Commands and Utilities-5

• Miscellaneous stuff
• Forcing a process in background (, fg, bg)
• Setting aliases
• Online manual pages, man
• Concept of NIS and NFS
• Changing password, passwd (?yppasswd?)
• Searching for patterns, grep and regular
  expressions
• Working with files with special characters in
  names
• The file utility
• finger, who and rwho
• ps and kill
• Mail and mail clients, netscape, pine, emacs and
  mail
• startx, .Xclients and .xinitrc files
• Tips
• Instead of asking someone try man -k
• It is a good practice to stick to one shell (csh
  is available on all)

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Lunch Break
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Editors in UNIX-1

• What all is available, Vi, Emacs, Pico, Joe?,
  Nedit?
• Vi The king of all editors? Tutorial?
• Why learn vi?
• Getting in and out?
• Basic keys for editing
• Moving around, deleting, joining lines
• Repeating commands
• Search and replace
• Tips
• Vim is not Vi
• Learn the keypad scroll key combinations instead
  of arrow keys
• Vi is fast, try to make the best use of its
  capabilities

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Editors in UNIX-2

• Emacs Much more than an editor?
• Why learn Emacs? History, Tutorial
• Getting in and out?
• Basic keys for editing
• Moving around, deleting a line
• Search and replace
• Formatted text, postscript spooling
• mail in emacs
• Syntax highlighting and templates
• Tips
• Emacs recognizes 20 languages out of the box
• Emacs is slow
• Emacs is not available by default on all unices

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Editors in UNIX-3

• Pico Is there really a need?
• Pico and Pine
• Editor Keys
• Joe?, Nedit?
• Keys similar to Norton Editor
• Nedit has some features similar to Emacs
• Tips
• Dont fall for Pico or Nedit
• Learn Vi and Emacs if you really want to get into
  UNIX
• In the end it is a matter of choice

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Programming on UNIX-1

• Is programming on UNIX tough? What all is
  available?
• Concept of IDE and differences with TurboC
• Compilers, Linkers, Debuggers and front-ends
• Managing big projects make and comparison with
  TC project file
• Example of a simple makefile
• GUI development on UNIX
• Java
• Tips
• UNIX is a programmers paradise

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Programming on UNIX-2

• Gcc, The GNU C/C compiler
• Simplest possible way to use gcc ltfile-namegt
• Common options
• output filename -o
• compile only -c
• Warnings -Wall
• optimizations -O1,2,3,4
• Debug -g
• Linking -lltlibrary-namegt
• Tips
• Not every UNIX systems will have gcc
• Turning on optimization makes the compilation
  slow
• Debugging and optimizing donot go together

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Programming on UNIX-3

• Ld, The Linker
• What exactly are libraries?
• Shared and static libraries
• Is there a need to call Ld explicitly?
• Passing options to Ld from gcc
• The -l option
• The -L option
• The LD_LIBRARY_PATH environment variable
• The LD_RUN_PATH environment variable
• Tips
• Always check the Ld on the system, HP-UX doesnt
  use GNU Ld
• Environment variables are different with non GNU
  Ld

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Programming on UNIX-4

• Gdb, The GNU C/C debugger
• Why is a debugger needed?
• gdb and ?core? File
• Common commands
• list
• run, break, resume
• backtrace and where
• Tips
• Using gdb directly might be tedious
• Try the various front-ends to gdb emacs, xxgdb,
  mxgdb etc.
• Not every system will have gdb, you just might
  have to use ?dbx?

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Programming on UNIX-5

• Gmake or GNU make
• What is the need for a Makefile?
• Dependencies
• Targets in a makefile
• Patterns in makefile
• Automatic variables in a makefile
• Pattern substitution
• Common target names all, clean, docs
• Tips
• Never forget the TAB
• Make is language independent!

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Programming on UNIX-6

• Example of a makefile
• CCgcc
• COPTS -g -Wall
• TARGETrun.x
• SRCShello.c junk.c
• OBJS(SRCS.c.o)
• all(OBJS)
• (CC) (COPTS) (OBJS) -o (TARGET)
• clean
• rm -f (OBJS) core
• .o.c
• (CC) (COPTS) -c lt

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Programming on UNIX-7

• GUI in UNIX?
• Differences with TurboC
• Vanilla X windows programming, why not?
• TCL/Tk
• Widget libraries
• Motif
• GTK
• QT, etc.
• Tips
• Always provide a command line interface to your
  programs
• Using a GUI is slow

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Programming on UNIX-8

• Java
• What is really different with the windows
  version?
• Is Jfc, Java2D, Java3D available?
• IDEs for Java over UNIX?
• Tips
• Dont try to use a .class dependency with make
• If you run Java from a server, graphics would be
  slow

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Introduction to Shell Programming-1

• What is the need for shell programming?
• Bourne shell (sh, ksh, zsh and bash)
• c shell (csh, tcsh)
• Examples of shell programming
• Moving all a.i.txt files to a.i1.txt
• Cleaning up your directory at the end of a day
• Tips
• Perl just might be a better option
• Dont forget ?sed? and ?awk?

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Introduction to Shell Programming-2

• Moving files script
• !/bin/sh -f
• FILE_LISTls grep "\.0-9\."
• for CURR_FILE in FILE_LIST do
• FIRST_NMecho CURR_FILE cut -d'.' -f1
• NUMecho CURR_FILE cut -d'.' -f2
• SECOND_NMecho CURR_FILE cut -d'.' -f3
• NUM_PLUSexpr NUM 1
• mv -i CURR_FILE FIRST_NM.NUM_PLUS.SECOND_
  NM
• done

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Introduction to Shell Programming-3

• Cleanup directory script
• !/bin/csh -f
• Assume that ps, pdf etc. directories are
  present
• set FILE_LISTls
• foreach CURR_FILE ( FILE_LIST )
• set TSTecho CURR_FILE grep \.pdf\
• if( TST ! "" ) then
• mv CURR_FILE pdf
• endif
• set TSTecho CURR_FILE grep \.ps\
• if( TST ! "" ) then
• mv CURR_FILE ps
• endif
• end

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Text formatting using UNIX-1

• What is the need for text formatting?
• WYSWYG or NOT?
• LaTeX Emacs PS renderer
• LaTeX WYSWYG front-end Lyx
• Other text formatters ?troff?
• How to make Presentations? Slides?
• Tips
• PowerPoint is still the best software for making
  presentations
• It is easy to convert PowerPoint slides to html

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Text formatting using UNIX-2

• LaTeX
• origin LaTeX and TeX
• usage
• LaTeX tutorials and manuals
• A not so short introduction to LaTeX
• The LaTeX manual
• LaTeX by Lesslie Lamport
• Lyx a WYSWIG interface to LaTeX
• Emacs ps-renderer and troff
• Tips
• For small formatted text Emacs is still the best

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Before wrapping up
Any questions/doubts which you would like to
clarify?
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Wrapping up

• Self help is the best help!
• The UNIX man pages. ?Manual sections?
• Using man, whatis etc.
• Experiment. You can never kill the system.
• Links
• http//www.gnu.org, for GNU tools and manuals
• http//sunsite.unc.edu, worlds largest
  collection of free software
• http//upavan.cse.iitd.ernet.in, Philips Lab.
  internal page
• http//poorvi.cse.iitd.ernet.in/local, Intel
  cluster archives
• Books
• The UNIX programming environment, Kernighan Pike

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Thank You