Update: Whoops. Ulrich Drepper told me there is already the "getconf" tool. Too bad I couldn't find it. Basically it's the same tool, only you don't need the _SC, _PC, or _CS prefix on the name, but you can't do a "--all" or "--verbose".
For more details, see the man page.
Released under the GNU General Public License.
Latest version: sysconf-1.0.0 (2003-12-13)