The danger with many packages is that unwanted files are added to the running system during the build process. To prevent this, use build, which creates a defined environment in which the package is built. To establish this chroot environment, the build script must be provided with a complete package tree. This tree can be made available on the hard disk, via NFS, or from DVD. Set the position with build --rpms directory. Unlike rpm, the build command looks for the SPEC file in the source directory. To build wget (like in the above example) with the DVD mounted in the system under /media/dvd, use the following commands as root:
cd /usr/src/packages/SOURCES/ mv ../SPECS/wget.spec . build --rpms /media/dvd/suse/ wget.spec
Subsequently, a minimum environment is established at /var/tmp/build-root. The package is built in this environment. Upon completion, the resulting packages are located in /var/tmp/build-root/usr/src/packages/RPMS.
The build script offers a number of additional options. For example, cause the script to prefer your own RPMs, omit the initialization of the build environment, or limit the rpm command to one of the above-mentioned stages. Access additional information with build --help and by reading the build man page.