NAME

       ldconfig - configure dynamic linker run-time bindings

SYNOPSIS

       /sbin/ldconfig [-nNvXV] [-f conf] [-C cache] [-r root] directory...
       /sbin/ldconfig -l [-v] library...
       /sbin/ldconfig -p

DESCRIPTION

       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  will  attempt  to deduce the type of ELF libraries (i.e., libc5 or libc6/glibc) based on what C
       libraries, if any, the library was linked against.

       Some existing libraries 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 used
       only for those ELF libraries 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.

OPTIONS

       -c fmt, --format=fmt
              (Since glibc 2.2) Cache format to use: old, new, or compat (default).

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

       -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

       /lib/ld.so
              Run-time linker/loader.
       /etc/ld.so.conf
              File containing a list of directories, one per line, 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, as well as those found in the trusted directories.

SEE ALSO

       ldd(1), ld.so(8)

COLOPHON

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       information  about  reporting  bugs,  and  the  latest  version  of  this   page,   can   be   found   at
       https://www.kernel.org/doc/man-pages/.