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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.  ldcon-
     fig 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

1. c fmt, –format=fmt

(Since glibc 2.2) Cache format to use: old, new, or compat

            (default).

1. C cache

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

1. f conf

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

1. i, –ignore-aux-cache

(Since glibc 2.7) Ignore auxiliary cache file.

1. l (Since glibc 2.2) Library mode. Manually link individual

libraries. Intended for use by experts only.

1. 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.

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

still updated.

1. p, –print-cache

Print the lists of directories and candidate libraries stored in

            the current cache.

1. r root

Change to and use root as the root directory.

1. 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.

1. V, –version

Print program version.

1. 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 direc-
            tories 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 4.16 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)