/etc/ld.so.conf-ldconfig creates the necessary links and cache to the most recent shared libraries found in the directories specified on the command line, in the file /etc/ld.so.conf, and in the trusted directories (/lib and /usr/lib). the cache is used by the run-time linker, ld.so or ld-linux.so. ldconfig checks the header and file names of the libraries it encounters when determining which versions should have their links updated. some files: /lib/ld.so run-time linker/loader /etc/ld.so.conf file containing a list of colon, space, tab, newline, or comma spearated directories in which to search for libraries. /etc/ld.so.cache file containing an ordered list of libraries found in the directories specified in /etc/ld.so.conf.