LDCONFIG(8)                                                  Linux Programmer's Manual                                                 LDCONFIG(8)

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

       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU                                                                 2017-09-15                                                         LDCONFIG(8)