Unix for Beginners
Unix Shell Programming
Unix Useful References
Unix Useful Resources
Copyright © 2014 by tutorialspoint
ldconfig - Unix, Linux Command
/sbin/ldconfig - configure dynamic linker run time bindings
-f conf ]
-C cache ]
-r root ]
/sbin/ldconfig -l [
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
/usr/lib). The cache is used by the run-time linker,
ld-linux.so. ldconfig checks the header and filenames of the libraries it encounters when
determining which versions should have their links updated.
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
ldconfig should normally be run by the superuser as it may require write
permission on some root owned directories and files.
Print current version number, the name of each directory as it
is scanned, and any links that are created.
Overrides quiet mode.
Only process directories specified on the command line.
Dont process the trusted directories
/usr/lib) nor those specified in
Dont rebuild the cache.
-X is also specified, links are still updated.
Dont update links.
-N is also specified, the cache is still rebuilt.
-f conf ||
conf instead of
-C cache ||
cache instead of
-r root ||
Change to and use
root as the root directory.
Library mode. Manually link individual libraries. Intended for
use by experts only.
Print the lists of directories and candidate libraries stored in
the current cache.
File containing a list of colon, space, tab, newline, or comma-separated
directories in which to search for libraries.
File containing an ordered list of libraries found in the directories