Linux [Electronic resources] نسخه متنی

Finding Packages on the Internet

You want to perform a task, but your current software doesn't seem to do it. After googling the Web and consulting with peers, you have the name of a package that you believe will do the job. It may be a new package or an updated version of your current software. First, determine that the package is not on your system. RPM gives you a list of all packages installed when you type:

rpm -qa | more

The list displays one page at a time. If the package is not installed, is not on your distribution CDs, and is not at the distribution Web site, you need to look for the package on the Internet. Most software has a home Web site where you can get information about the package and its dependencies and download the latest version.

Often, using the software name in a URL will find the package home site. For instance, the superuseful package may be found at www.superuseful.com or www.superuseful.org. If not, you can google to find the Web site.

The download format varies. For instance, the home Web site for MySQL, an open source database, provides download files in the following formats:

• Binaries :
  Compiled, ready-to-run files that just need to be copied to the correct location on your system. Often the binary distribution consists of more than one file, but the files are compressed into one file, called a tarball because it's created using the tar command.

• RPMs :
  RPMs for specific distributions may be available, particularly for popular distributions such as Fedora. Or, a generic RPM for Linux may be available. RPMs are installed using the RPM command-line tool, described later in this chapter. An RPM package has a filename that ends with .rpm.

• Source code :
  Source files that you download and compile on your system. Instructions for installing software from source code are provided later in this chapter. Source code consists of several files compressed into a single file, called a tarball.

Many packages are available in RPM repositories maintained on the Web. You can search for packages, check their dependencies, and download all the software needed in one stop. However, packages in repositories are generally a version or two behind the packages available on the home Web site. Some repositories are:

www.rpmfind.net
freshrpms.net
dries.studentenweb.org/apt/