Wiley 978-0-7645-7644-7 Datasheet

SoftwareManagementThe basic unit of software in Debian— and, indeed, inalmost every major operating system today — is thepackage. A lot of effort goes

80Part I ✦ The Fundamentalsdpkg can also display which files are part of a given package and search for whichpackage owns a particular file. These act

81Chapter 4 ✦ Software ManagementFigure 4-1: aptitude’s main display.3. Aside from the categories shown in Figure 4-1, at times others will appear,suc

82Part I ✦ The FundamentalsDon’t quit aptitude yet because we’ll examine the ed package in more detail laterin this chapter.Showing package detailsOf

83Chapter 4 ✦ Software ManagementDepends: libc6 (>= 2.3.1-1)Filename: pool/main/e/ed/ed_0.2-20_i386.debSize: 44718MD5sum: 0c466ce6a160c62fa558fbbb4

84Part I ✦ The Fundamentalsslash key tells aptitude that you will be typing in a term to search for. This termwill be searched for in all packages’ na

85Chapter 4 ✦ Software ManagementInstalling PackagesNow that you know how to find packages, you likely want to install some. I’ll useseveral example p

86Part I ✦ The FundamentalsThe output you get won’t be identical to the output here, but it should be close. Ifyou get any errors, chances are your /e

87Chapter 4 ✦ Software Managementhostname:~# apt-cache show mutt | grep –E ‘^(Depends|Recommends)’Depends: libc6 (>= 2.3.2.ds1-4), libidn11, libncu

88Part I ✦ The FundamentalsSetting up mime-support (3.26-1) ...Setting up mutt (1.5.5.1-20040112+1) ...Setting up libsasl2-modules (2.1.18-2) ...Readi

89Chapter 4 ✦ Software ManagementRemoving and Purging PackagesIn Debian, great pains are taken to ensure that configuration data is kept intact.When a

72Part I ✦ The FundamentalsSource packages versus binary packagesA source package is a package that is made up completely of source code. Sourcecode i

90Part I ✦ The FundamentalsPurging configuration files for vim ...hostname:~# ls /etc/vim/ls: /etc/vim/: No such file or directoryhostname:~#apt-get a

91Chapter 4 ✦ Software ManagementAs you can see, the packages that were installed alongside mutt were also removedwhen you asked for mutt’s removal. T

92Part I ✦ The Fundamentalsbut you can also invoke them later on to reconfigure the package. This is done byrunning dpkg-reconfigure packagename:hostn

93Chapter 4 ✦ Software ManagementLet’s take a working example, and reinstall vim. If you haven’t purged it already, doso now with aptitude purge vim.

94Part I ✦ The FundamentalsSince the configuration file you created is fake, press Y and press Enter to use thepackaged version. The installation will

95Chapter 4 ✦ Software ManagementIf there are a number of upgrades available but you want to upgrade only one ormore specific packages, you can instea

96Part I ✦ The FundamentalsPackage Repositories and /etc/apt/sources.listAlthough Debian’s package repositories are very large and complete, they don’

97Chapter 4 ✦ Software ManagementSometimes the default is not good enough. apt’s “pinning” feature lets you changeit. Here are a few scenarios where y

98Part I ✦ The FundamentalsCandidate: 1:1.3.4-1Version Table:1:1.3.4-1 0500 http://http.us.debian.org sid/main Packages500 http://http.us.debian.org e

99Chapter 4 ✦ Software ManagementEach stanza of this file consists of several fields, each on their own line. (Within astanza, fields don’t need to be

73Chapter 4 ✦ Software ManagementBinary packages are not without their drawbacks, however. Notably, they tend torequire more ancillary software to be

100Part I ✦ The Fundamentalskword? You can temporarily override your pinning preferences with apt-get’s --target-releaseoption (synonyms are -t and --

101Chapter 4 ✦ Software ManagementYou can also override version preferences on the apt-get command line like this:# apt-get install kword=1:1.3.4-1And

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74Part I ✦ The Fundamentalsmost users find the most compelling aspect of Debian to be its package manage-ment system. This subsection discusses its pa

75Chapter 4 ✦ Software ManagementMaintaining package relationships is a large part of a Debian maintainer’s jobbecause these relatively simple concept

76Part I ✦ The FundamentalsPackage repositoriesPackage repositories are large archives of packages that are stored, usually on theInternet, for users

77Chapter 4 ✦ Software Managementapt-get, however, is just one part of the apt family. apt-cache, for example,is the apt family’s command-line search

78Part I ✦ The FundamentalsListing installed packagesListing installed packages is a pretty easy task, and you can use either dpkg oraptitude to do it

79Chapter 4 ✦ Software Managementto lose power during a package maintenance session, the database would be left inan inconsistent state. There’s actua