LDCONFIG(8) Linux Programmer's Manual LDCONFIG(8)
/sbin/ldconfig - configure dynamic linker run time bindings
/sbin/ldconfig [ -nNvXV ] [ -f conf ] [ -C cache ] [ -r root ] direc-
/sbin/ldconfig -l [ -v ] library ...
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 filenames of the libraries it
encounters when determining which versions should have their links
ldconfig will attempt to deduce the type of ELF libs (ie. libc5 or
libc6/glibc) based on what C libs, if any, the library was linked
against. Therefore, when making dynamic libraries, it is wise to
explicitly link against libc (use -lc).
Some existing libs do not contain enough information to allow the
deduction of their type. Therefore, the /etc/ld.so.conf file format
allows the specification of an expected type. This is only used for
those ELF libs which we can not work out. The format is "dirname=TYPE",
where TYPE can be libc4, libc5, or libc6. (This syntax also works on
the command line.) Spaces are not allowed. Also see the -p option.
ldconfig should normally be run by the superuser as it may require
write permission on some root owned directories and files.
-v Verbose mode. Print current version number, the name of each
directory as it is scanned, and any links that are created.
Overrides quiet mode.
-n Only process directories specified on the command line. Don't
process the trusted directories (/lib and /usr/lib) nor those
specified in /etc/ld.so.conf. Implies -N.
-N Don't rebuild the cache. Unless -X is also specified, links are
-X Don't update links. Unless -N is also specified, the cache is
Use conf instead of /etc/ld.so.conf.
Use cache instead of /etc/ld.so.cache.
Change to and use root as the root directory.
-l Library mode. Manually link individual libraries. Intended for
use by experts only.
-p Print the lists of directories and candidate libraries stored in
the current cache.
/lib/ld.so run-time linker/loader
/etc/ld.so.conf File containing a list of colon, space, tab, new-
line, or comma-separated 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.
GNU C Library 2002-05-06 LDCONFIG(8)