Prentice hall linux for programmers and users feb 2006 ISBN 0131857487

Tableof
•
Contents
• Index

LinuxforProgrammersandUsers
ByGrahamGlass,KingAbles
Publisher :PrenticeHall
PubDate :February15,2006
PrintISBN-10 :0-13-185748-7
PrintISBN-13 :978-0-13-185748-3
eTextISBN-10 :0-13-186102-6
eTextISBN-13 :978-0-13-186102-2
Pages :700


OfferingfullcoverageofLinuxinonesource,thisbookdocuments
themostcommonlyneededtopicsfornewandexperiencedLinux
usersandprogrammers.




LinuxforProgrammersandUsers
ByGrahamGlass,KingAbles
Publisher :PrenticeHall
PubDate :February15,2006
PrintISBN-10 :0-13-185748-7

PrintISBN-13 :978-0-13-185748-3
Tableof eTextISBN-10 :0-13-186102-6
•
Contents eTextISBN-13 :978-0-13-186102-2
• Index
Pages :700

Copyright
TrademarkInformation
Preface
AbouttheAuthors
AbouttheBook
OrganizationoftheBook
LayoutoftheChapters
AGuideforTeachers
Nomenclature

ReferencestoOtherBooks
SourceCodeAvailabilityOnline
Acknowledgments
Chapter1.WhatIsLinux?
Motivation
Prerequisites
Objectives
Presentation
Section1.1.ComputerSystems
Section1.2.Hardware
Section1.3.OperatingSystem
Section1.4.Software
Section1.5.SharingResources

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2
3
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5

Section1.6.Communication
Section1.7.Utilities
Section1.8.ProgrammerSupport
Section1.9.Standards
Section1.10.LinuxLineage
Section1.11.LinuxPackaging

Section1.12.TheLinuxandUNIXPhilosophy
Section1.13.LinuxFeatures
Section1.14.TheRestofThisBook
ChapterReview
Chapter2.InstallingYourLinuxSystem
Motivation
Prerequisites
Objectives
Presentation
Section2.1.Introduction
Section2.2.MakeSureYourHardwareWillSupportLinux
Section2.3.ChooseYourLinuxDistribution
Section2.4.ConsiderOptionalSoftwarePackages
Section2.5.DesignYourSystem
Section2.6.GetLinux
Section2.7.InstallLinux
ChapterReview
Chapter3.GNUUtilitiesforNonprogrammers
Motivation
Prerequisites
Objectives
Presentation
Utilities
Shellcommand
Section3.1.ObtaininganAccount
Section3.2.LoggingIn
Section3.3.Shells
Section3.4.RunningaGNUUtility
Section3.5.Input,Output,andErrorChannels
Section3.6.ObtainingOnlineHelp:man

Section3.7.SpecialCharacters
Section3.8.SettingYourPassword:passwd
Section3.9.LoggingOut

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Section3.10.PoetryinMotion:ExploringtheFileSystem
Section3.11.PrintingYourShell'sCurrentWorkingDirectory:pwd
Section3.12.AbsoluteandRelativePathnames
Section3.13.CreatingaFile
Section3.14.ListingtheContentsofaDirectory:ls
Section3.15.ListingtheContentsofaFile:cat/more/head/tail
Section3.16.RenamingaFile:mv
Section3.17.CreatingaDirectory:mkdir
Section3.18.MovingtoaDirectory:cd
Section3.19.CopyingaFile:cp
Section3.20.EditingaFile:vim
Section3.21.DeletingaDirectory:rmdir
Section3.22.DeletingaFile:rm
Section3.23.PrintingaFile:lp/lpstat/cancel
Section3.24.PrintingaFile:lpr/lpq/lprm
Section3.25.CountingWordsinaFile:wc
Section3.26.FileAttributes
Section3.27.Groups
Section3.28.ListingYourGroups:groups
Section3.29.ChangingaFile'sGroup:chgrp
Section3.30.ChangingaFile'sPermissions:chmod
Section3.31.ChangingaFile'sOwner:chown
Section3.32.ChangingGroups:newgrp
Section3.33.PoetryinMotion:Epilogue
Section3.34.DeterminingYourTerminal'sType:tset
Section3.35.ChangingaTerminal'sCharacteristics:stty
Section3.36.EditingaFile:vim

Section3.37.EditingaFile:emacs
Section3.38.ElectronicMail:mail
ChapterReview
Chapter4.GNUUtilitiesforPowerUsers
Motivation
Prerequisites
Objectives
Presentation
Utilities
Section4.1.Introduction
Section4.2.FilteringFiles:grep,egrep,fgrep,anduniq
Section4.3.SortingFiles:sort

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Section4.4.ComparingFiles:cmpanddiff
Section4.5.FindingFiles:find
Section4.6.ArchivingFiles:cpio,tar,anddump/restore
Section4.7.SchedulingCommands:crontabandat
Section4.8.ProgrammableTextProcessing:gawk
Section4.9.HardandSoftLinks:ln
Section4.10.IdentifyingShells:whoami
Section4.11.SubstitutingaUser:su
Section4.12.TransformingFiles
Section4.13.LookingatRawFileContents:od
Section4.14.MountingFileSystems:mountandumount
Section4.15.IdentifyingTerminals:tty
Section4.16.TimingExecution:time
Section4.17.RollingYourOwnPrograms:Perl
ChapterReview
Chapter5.TheLinuxShells
Motivation
Prerequisites

Objectives
Presentation
Utilities
ShellCommands
Section5.1.Introduction
Section5.2.SelectingaShell
Section5.3.ShellOperations
Section5.4.ExecutableFilesVersusBuilt-inCommands
Section5.5.Metacharacters
Section5.6.Redirection
Section5.7.FilenameSubstitution(Wildcards)
Section5.8.CommandSubstitution
Section5.9.Sequences
Section5.10.GroupingCommands
Section5.11.BackgroundProcessing
Section5.12.RedirectingBackgroundProcesses
Section5.13.ShellPrograms(Scripts)
Section5.14.SubshellsorChildShells
Section5.15.Variables
Section5.16.Quoting
Section5.17.HereDocuments

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187

Section5.18.JobControl
Section5.19.FindingaCommand:$PATH
Section5.20.SupersedingStandardUtilities
Section5.21.TerminationandExitCodes
Section5.22.CommonCoreBuilt-Ins
ChapterReview
Chapter6.TheBourneAgainShell
Motivation
Prerequisites
Objectives

Presentation
ShellCommands
Section6.1.Introduction
Section6.2.Startup
Section6.3.Variables
Section6.4.CommandShortcuts
Section6.5.TildeSubstitution
Section6.6.Redirection
Section6.7.CommandSubstitution
Section6.8.Arithmetic
Section6.9.ConditionalExpressions
Section6.10.ControlStructures
Section6.11.Functions
Section6.12.Menus:select
Section6.13.DirectoryAccessandtheDirectoryStack
Section6.14.JobControl
Section6.15.Command-LineOptions
ChapterReview
Chapter7.TheKornShell
Motivation
Prerequisites
Objectives
Presentation
ShellCommands
Section7.1.Introduction
Section7.2.Startup
Section7.3.Variables
Section7.4.Aliases
Section7.5.History

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Section7.6.EditingCommands
Section7.7.Arithmetic

Section7.8.TildeSubstitution
Section7.9.Menus:select
Section7.10.Functions
Section7.11.JobControl
Section7.12.Enhancements
Section7.13.SampleProject:junk
Section7.14.Command-LineOptions
ChapterReview
Chapter8.TheCShell
Motivation
Prerequisites
Objectives
Presentation
ShellCommands
Section8.1.Introduction
Section8.2.Startup
Section8.3.Variables
Section8.4.Expressions
Section8.5.FilenameCompletion
Section8.6.CommandEditing
Section8.7.Aliases
Section8.8.History
Section8.9.ControlStructures
Section8.10.SampleProject:junk
Section8.11.Enhancements
Section8.12.Built-Ins
Section8.13.TheDirectoryStack
Section8.14.Command-LineOptions
ChapterReview
Chapter9.NetworkingandtheInternet

Motivation
Prerequisites
Objectives
Presentation
Commands
Section9.1.Introduction
Section9.2.BuildingaNetwork

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Section9.3.Internetworking
Section9.4.IdentifyingNetworkUsers
Section9.5.CommunicatingwithNetworkUsers
Section9.6.DistributingData
Section9.7.DistributedProcessing
Section9.8.EvolutionoftheInternet
Section9.9.UsingToday'sInternet
ChapterReview
Chapter10.TheLinuxDesktop
Motivation
Prerequisites
Objectives
Presentation
Utilities
Section10.1.Introduction
Section10.2.XServers
Section10.3.DesktopEnvironments
Section10.4.WindowManagers
Section10.5.Widgets
Section10.6.DesktopOperation
Section10.7.ClientApplications
Section10.8.StandardXClientArguments
Section10.9.AdvancedTopics
ChapterReview

Chapter11.CProgrammingTools
Motivation
Prerequisites
Objectives
Presentation
Utilities
Section11.1.TheCLanguage
Section11.2.CCompilers
Section11.3.Single-ModulePrograms
Section11.4.MultimodulePrograms
Section11.5.ArchivingModules:ar
Section11.6.ManagingDependencies:make
Section11.7.TheGNUProfiler:gprof
Section11.8.DebuggingaProgram:gdb
Section11.9.WhenYou'reDone:strip

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ChapterReview
Chapter12.SystemsProgramming
Motivation
Prerequisites
Objectives
Presentation
Utilities
Systemcallsandlibraryfunctions
Section12.1.Introduction
Section12.2.ErrorHandling:perror()
Section12.3.RegularFileManagement
Section12.4.ProcessManagement
Section12.5.Signals
Section12.6.InterprocessCommunication
ChapterReview
Chapter13.LinuxInternals
Motivation

Prerequisites
Objectives
Presentation
Section13.1.Introduction
Section13.2.KernelBasics
Section13.3.TheFileSystem
Section13.4.ProcessManagement
Section13.5.VirtualMemoryManagement
Section13.6.InputandOutput
Section13.7.InterprocessCommunication
ChapterReview
Chapter14.SystemAdministration
Motivation
Prerequisites
Objectives
Presentation
Utilities
Section14.1.Introduction
Section14.2.BecomingtheSuper-User
Section14.3.StartingLinux
Section14.4.StoppingLinux
Section14.5.MaintainingtheFileSystem

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Section14.6.MaintainingUserAccounts
Section14.7.InstallingNewSoftware
Section14.8.PeripheralDevices
Section14.9.TheNetworkInterface
Section14.10.AutomatingTasks
Section14.11.TunableKernelParameters
Section14.12.SecurityIssues
ChapterReview
AppendixA.
SectionA.1.RegularExpressions
SectionA.2.ExtendedRegularExpressions
SectionA.3.ModifiedBackus-NaurNotation
SectionA.4.UtilitiesandShellBuilt-InCommands
SectionA.5.SystemCallsandLibraryFunctions
Bibliography
Index

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Copyright
[Pageiv]
LibraryofCongressCataloging-in-PublicationData
Onfile
VicePresidentandEditorialDirector,ECS:MarciaJ.
Horton
ExecutiveEditor:TracyDunkelberger
AssistantEditor:CaroleSnyder
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©2006PearsonEducation,Inc.
PearsonPrenticeHall
PearsonEducation,Inc.
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Allrightsreserved.Nopartofthisbookmaybereproducedin
anyformorbyanymeans,withoutpermissioninwritingfrom
thepublisher.
PearsonPrenticeHall®isatrademarkofPearsonEducation,
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Theauthorandpublisherofthisbookhaveusedtheirbest
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development,research,andtestingofthetheoriesand
programstodeterminetheireffectiveness.Theauthorand
publishermakenowarrantyofanykind,expressedorimplied,


withregardtotheseprogramsorthedocumentationcontained
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PearsonEducation,Inc.,UpperSaddleRiver,NewJersey

[Pagev]

Dedication
Toallthosewhoworktoleaveourworldalittlebetter
thantheyfoundit.




[Pageii]


TrademarkInformation
AIX®,IBM,PowerPC®,andRS/6000®areregistered
trademarksofInternationalBusinessMachinesCorporation.
Alpha,DEC,OpenVMS,Vax,andVMSaretrademarksof
COMPAQComputerCorporationandHewlett-PackardCompany.
AMDisaregisteredtrademarkofAdvancedMicroDevices,Inc.
BSDisaregisteredtrademarkofBerkeleySoftwareDesign,Inc.
EthernetisaregisteredtrademarkofXeroxCorporation.
DebianisatrademarkofSoftwareinthePublicInterest,Inc.

Fedora™andRedHataretrademarksofRedHat,Inc.
GNOMEisatrademarkoftheGNOMEFoundation,Inc.
GNUisatrademarkoftheFreeSoftwareFoundation.
Intel®,Itanium™,andPentium®areregisteredtrademarksof
IntelCorporation.
IRIX®isaregisteredtrademarkofSiliconGraphics,Inc.
Java™isatrademarkofSunMicrosystems,Inc.
KDEandKDesktopEnvironmentaretrademarksofKDEe.V.
LinuxisaregisteredtrademarkofLinusTorvalds.
Macintosh®andMacOSareregisteredtrademarksofApple
Computer,Inc.


Microsoft®Windows,WindowsNT,andWindows2000are
registeredtrademarksofMicrosoftCorporation.
MIPSisatrademarkofMIPSTechnologies,Inc.
MosaicisaproprietarytrademarkoftheUniversityofIllinois.
MotifandOSFareregisteredtrademarksandtheOpenGroupis
atrademarkofTheOpenGroup.
Netscape,andNetscapeNavigatorareregisteredtrademarksof
NetscapeCommunicationsCorporation.
NFS,OpenWindows,andSPARCaretrademarksofSun
Microsystems,Inc.AllSPARCtrademarksareusedunder
licenseandaretrademarksorregisteredtrademarksofSPARC
International,Inc.
NovellisaregisteredtrademarkofNovell,Inc.
PA-RISCisaregisteredtrademarkofHewlett-PackardCompany.
PartitionMagicisaregisteredtrademarkofSymantec
Corporation.
SCOandUnixwarearetrademarksofCaldera.

SlackwareisaregisteredtrademarkofPatrickVolkerdingand
SlackwareLinux,Inc.
Solaris™isatrademarkofSunMicrosystems,Inc.
SunSoft™isatrademarkofSunriseIndustries,Incorporated.
Sunand$$$MicrosystemsaretrademarksofSun
Microsystems,Inc.
SuSEisaregisteredtrademarkofSuSELinuxAG.


TurbolinuxisatrademarkofTurbolinux,Inc.
UNIXandXWindowSystemareregisteredtrademarksofThe
OpenGroup.
VMwareisatrademarkofVMware,Inc.
HPVUEisaregisteredtrademarkofHewlett-PackardCompany.
Windows,Windows95,Windows98,WindowsME,WindowsNT,
Windows2000,andWindowsXParetrademarksofMicrosoft
Corporation.
XFree86isaregisteredtrademarkofTheXFree86Project,Inc.
XFS®isaregisteredtrademarkofSiliconGraphics,Inc.
Allothertrademarksandcopyrightsappearinginthisbookare
thepropertiesoftheirrespectiveowners.




[Pagexxv]


Preface
AbouttheAuthors

AbouttheBook
OrganizationoftheBook
LayoutoftheChapters
AGuideforTeachers
Nomenclature
ReferencestoOtherBooks
SourceCodeAvailabilityOnline
Acknowledgments


[Pagexxv(continued)]

AbouttheAuthors
GrahamGlassgraduatedfromtheUniversityofSouthampton,
England,withaBachelor'sdegreeinComputerScienceand
Mathematics.HeimmigratedtotheUnitedStatesandobtained
hisMaster'sdegreeinComputerSciencefromtheUniversityof
TexasatDallas.HethenworkedasaUNIX/Csystemsanalyst
andbecameheavilyinvolvedwithresearchinneuralnetworks
andparalleldistributedprocessing.Helatertaughtatthe
UniversityofTexasatDallas,coveringawidevarietyofcourses
includingUNIX,C,assemblylanguage,programminglanguages,
C++,andSmalltalk.Heco-foundedObjectSpace,which
specializedinobject-orientedtraining,consulting,andproducts.
HethenfoundedTheMindElectric,whichproducedaJavaweb
servicesplatformcalledGlueandaplatformforsharedSOA
infrastructurecalledFabric.TheMindElectricwasacquiredby
webMethods,whereGrahamisnowtheChiefTechnology
Officer.Inhissparetime,hereads,runs,swims,cycles,dives,
skis,travels,andmaintainsablog.

KingAblesearnedhisBachelor'sdegreeinComputerScience
fromtheUniversityofTexasatAustinin1982.Hehasbeena
UNIXuser,developer,systemsadministrator,orconsultantsince
1979andaLinuxusersincelateinthelastcentury.Hehas
workedinacademia,atsmallstartupcompanies,andinlarge
corporations,andiscurrentlyanindependentconsultant
specializinginITservicesandnetworksecurity.Hehas
developedUNIXandLinuxproductsoftwareandsystemstools,
deliveredsupportandtrainingservices,andwrittenproduct
documentationandtrainingmaterials.HehasauthoredorcoauthoredtwobooksonUNIX,writtenmanymagazinearticles
onvariousUNIXtopics,andisaco-inventorofane-commerce
privacymechanismthatwasawardedasoftwarepatent.His
professionalinterestsincludenetworking,security,andprivacy,


buthelikeshiking,mountainbiking,andskiingjustabitmore.




[Pagexxvi]

AbouttheBook
ThisbookisanoutgrowthofthepopularityofLinux.Itsoriginal
version,UNIXforProgrammersandUsers,writtenbyGraham
andupdatedinsubsequenteditionsbyKinghasbeenwidely
usedinclassroomsettingsandispopularwithprofessionals
newtoUNIXorUNIXprogramming.Theincreasingpopularityof
LinuxcreatedademandforaLinuxversionofsuchabook,
especiallyinclassroomswhereLinuxisemergingasthe

platformofchoiceforcomputersciencestudents.
Grahamwrotetheoriginalversioninresponsetotheneedfor
coursematerialforuniversitystudentsaswellasprofessional
programmers,takinggreatcaretoincludemanydifferenttypes
ofusersinhistargetaudience.Hecreatedabookthatwas
helpfultoeveryonefromacompletebeginnertoanexperienced
programmerandallowedinstructorstoteachavarietyof
courses.ThewidespreaduseofLinuxhasledtothesameneed
forLinuxusersandinstructors.
WhenmyeditorsatPrentice-Hallfirstapproachedmeabout
creatingaLinuxversionofthebook,myflippantresponsewas
"Fine,change'UNIX'to'Linux'onthecoverandshipit!"That
responsewasmadeinjest,ofcourse,butIalsothoughtitwas
rootedinsomeamountoftruth.Ihadusedmanyversionsof
bothUNIXandLinuxinthepastseveralyears,andthey
seemedallthesametome(whichisastrengthofbothLinux
andUNIX).Butthissimilarityisonlyskindeep.
ExperiencedUNIXuserswillfeelverycomfortablewithLinux
becauseitadherestoaspecifiedstandardforportable
operatingsystems,whichmeansthatitprovidesaspecificset
ofcommands,applications,libraryfunctions,andsystemcalls.
Mostofthecommandsandsystemcallsbehavesimilarlyto,if
notexactlythesameas,thoseinmostversionsofUNIX.Some


Linuxcommandshavebeenrenamedforvariousreasons,butin
mostcasestheoldUNIXnameisusuallyavailableasan
equivalent.
While,onthesurface,LinuxlooksjustlikeUNIX(whichisthe
wholeideabehindhavingastandard),theimplementationis

anotherstory.Withthebenefitofthousandsofvolunteer
programersunencumberedbymarketingdepartmentsand
productreleaseschedules(i.e.,"businessissues")butarmed
withyearsofadvancesinoperating-systemsunderstanding,
Linuxisactuallyasignificantimprovementofanalreadygood
idea.Whenyoulook"underthehood,"youwillfindthatLinux
isamuchcleanerimplementationbecauseitdoesn'tsufferfrom
thelongevolutionandtangledcodebasethatplaguesmany
versionsofUNIXtoday.
AndsothisLinux-specificbookisactuallyverydifferentfromits
UNIXcounterpart.EvenwherethesubstanceissimilartoUNIX,
thedetailsandexamplesmayvarygreatly.Substantive
differencesincludeanewchapteroninstallingLinuxandlargely
revisedchaptersontheinternalworkingsofLinuxandsystem
administration.
Whilewecouldnotpossiblycovereverydetailofevery
commandorapplicationthatcomeswithLinux(without
creatingamultivolumeset!),wetrytocoverthebasicsandthe
mostoftenusedutilitiestoprovideasolidfoundationupon
whichyoucancontinuetobuildyourunderstandingofLinux
andtheGNUutilities.


[Pagexxvii]

OrganizationoftheBook
Linuxisabigthing.Todescribeitfullyrequiresanexplanation
ofmanytopicsfromdifferentangles,whichisexactlywhatI've
provided.Thisbookissplitintoseveralsections,eachdesigned
foraparticularkindofuser.Irecommendthatthevarious

categoriesofuserreadthechaptersasfollows:
Categoryofuser

Chapters

Day-to-daycasual
users

Chapter1,"WhatIsLinux?"




Advancedusers

Chapter2,"InstallingYourLinuxSystem"(if
necessary)
Chapter3,"GNUUtilitiesforNonprogrammers"
Thepreviouschaptersand:
Chapter4,"GNUUtilitiesforPowerUsers"
Chapter5,"TheLinuxShells"
yourchoiceofshellchapter(s)
Chapter9,"NetworkingandtheInternet"
Chapter10,"TheLinuxDesktop"

Applications
programmers

Theabovechaptersand:
•Chapter11,"CProgrammingTools"

•Chapter12,"SystemsProgramming"

Wizards

Everything(ofcourse!)