ldconfig(8)



ldconfig(8)                                                        ldconfig(8)

NAME
       ldconfig - configure dynamic linker run-time bindings

SYNOPSIS
       ldconfig [OPTION...]

DESCRIPTION
       ldconfig  creates,  updates,  and removes the necessary links and cache
       (for use by the run-time linker,  ld.so)  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  and
       /lib).   ldconfig  checks the header and file names of the libraries it
       encounters when determining which  versions  should  have  their  links
       updated.   ldconfig ignores symbolic links when scanning for libraries.

       ldconfig will attempt to deduce the type of ELF libs (ie. libc  5.x  or
       libc  6.x  (glibc))  based  on  what C libraries if any the library was
       linked against, therefore when making dynamic libraries, it is wise  to
       explicitly link against libc (use -lc).  ldconfig is capable of storing
       multiple ABI types of libraries into a single  cache  on  architectures
       which  allow  native running of multiple ABIs, like ia32/ia64/x86_64 or
       sparc32/sparc64.

       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 like this
       "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.

       Directory names containing an = are no longer legal  unless  they  also
       have an expected type specifier.

       ldconfig  should  normally  be  run by the super-user as it may require
       write permission on some root owned directories and files. If  you  use
       -r option to change the root directory, you don't have to be super-user
       though as long as you have sufficient right to that directory tree.

OPTIONS
       -v --verbose
              Verbose mode.  Print current version number, the  name  of  each
              directory as it is scanned and any links that are created.

       -n     Only  process  directories specified on the command line.  Don't
              process the trusted directories (/usr/lib and  /lib)  nor  those
              specified in /etc/ld.so.conf.  Implies -N.

       -N     Don't rebuild the cache.  Unless -X is also specified, links are
              still updated.

       -X     Don't update links.  Unless -N is also specified, the  cache  is
              still rebuilt.

       -F --force
              Generate cache even if it looks up-to-date.

       -f conf
              Use conf instead of /etc/ld.so.conf.

       -C cache
              Use cache instead of /etc/ld.so.cache.

       -r root
              Change to and use root as the root directory.

       -l     Library mode.  Manually link individual libraries.  Intended for
              use by experts only.

       -p --print-cache
              Print the lists of directories and candidate libraries stored in
              the current cache.

       -c --format=FORMAT
              Use  FORMAT  for the cache file. Choices are old, new and compat
              (the default).

       -? --help --usage
              Print usage information.

       -V --version
              Print version and exit.

EXAMPLES
              # /sbin/ldconfig -v
       will set up the correct links for the shared binaries and  rebuild  the
       cache.
              # /sbin/ldconfig -n /lib
       as  root  after  the installation of a new shared library will properly
       update the shared library symbolic links in /lib.

FILES
       /lib/ld-linux.so.*  execution 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.
                           This file is not in human readable format,  and  is
                           not intended to be edited.
       lib*.so.version     shared libraries

SEE ALSO
       ldd(1), ld.so(8).

BUGS
       ldconfig,  being  a user process, must be run manually and has no means
       of dynamically determining and relinking shared libraries  for  use  by
       ld.so when a new shared library is installed.

AUTHORS
       Andreas  Jaeger.  Manual page written by David Engel and Mitch D'Souza.

                                27 August 2006                     ldconfig(8)

Man(1) output converted with man2html
list of all man pages