-The configure script will automatically enable support for a compressed
-pci.ids if you have zlib installed. You can override its guess by using
-"make ZLIB=no" or "make ZLIB=yes". If compressed support is enabled,
-pciutils will use pci.ids.gz in preference to pci.ids, even if the
-pci.ids file is newer. If the pci.ids.gz file is missing, it will use
-pci.ids instead.
+There are several options which can be set in the Makefile or overridden
+when running make:
+
+ ZLIB=yes/no Enable support for compressed pci.ids (requires zlib).
+ If it is enabled, pciutils will use pci.ids.gz in preference to
+ pci.ids, even if the pci.ids file is newer. If the pci.ids.gz
+ file is missing, it will use pci.ids instead. If you do not
+ specify this option, the configure script will try to guess
+ automatically based on the presence of zlib.
+
+ DNS=yes/no Enable support for querying the central database of PCI IDs
+ using DNS. Requires libresolv (which is available on most
+ systems as a part of the standard libraries) and tries to
+ autodetect its presence if the option is not specified.
+
+ SHARED=yes/ Build libpci as a shared library. Requires GCC 4.0 or newer.
+ no/local The ABI of the shared library is intended to remain backward
+ compatible for a long time (we use symbol versioning to achieve
+ that, like GNU libc does). The value `local' includes the
+ right directory name in the binaries, so the utilities can be
+ run without installation. This is not recommended for any
+ production builds.
+
+"make install-lib" installs the library together with its header files
+for use by other programs.