ldconfig(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | SEE ALSO

ldconfig(8)              System Manager's Manual             ldconfig(8)

NAME         top

       ldconfig - configure dynamic linker run-time bindings

SYNOPSIS         top

       /sbin/ldconfig [-nNvVX] [-C cache] [-f conf] [-r root]
                      directory ...

       /sbin/ldconfig -l [-v] library ...

       /sbin/ldconfig -p

DESCRIPTION         top

       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.  On some 64-bit architectures
       such as x86-64, /lib and /usr/lib are the trusted directories for
       32-bit libraries, while /lib64 and /usr/lib64 are used for 64-bit
       libraries.

       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 updated.  ldconfig should normally be run by the superuser
       as it may require write permission on some root owned directories
       and files.

       ldconfig will look only at files that are named lib*.so* (for
       regular shared objects) or ld-*.so* (for the dynamic loader
       itself).  Other files will be ignored.  Also, ldconfig expects a
       certain pattern to how the symbolic links are set up, like this
       example, where the middle file (libfoo.so.1 here) is the SONAME
       for the library:

           libfoo.so -> libfoo.so.1 -> libfoo.so.1.12

       Failure to follow this pattern may result in compatibility issues
       after an upgrade.

OPTIONS         top

       -c fmt
       --format=fmt
              (Since glibc 2.2) Use cache format fmt, which is one of
              old, new, or compat.  Since glibc 2.32, the default is
              new.  Before that, it was compat.

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

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

       -i
       --ignore-aux-cache
              (Since glibc 2.7) Ignore auxiliary cache file.

       -l     (Since glibc 2.2) Interpret each operand as a library name
              and configure its links.  Intended for use only by
              experts.

       -n     Process only the directories specified on the command
              line; don't process the trusted directories, 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.

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

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

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

       -V
       --version
              Print program version.

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

FILES         top

       /lib/ld.so
              is the run-time linker/loader.
       /etc/ld.so.conf
              contains a list of directories, one per line, in which to
              search for libraries.
       /etc/ld.so.cache
              contains an ordered list of libraries found in the
              directories specified in /etc/ld.so.conf, as well as those
              found in the trusted directories.

SEE ALSO         top

       ldd(1), ld.so(8)

Linux man-pages (unreleased)     (date)                      ldconfig(8)

Pages that refer to this page: dpkg-divert(1)ldd(1)dlopen(3)rtld-audit(7)ld.so(8)sln(8)