LDCONFIG(8)             FreeBSD System Manager's Manual            LDCONFIG(8)

NAME
     ldconfig - configure the dynamic linker search path for shared libraries

SYNOPSIS
     ldconfig [-32] [-Rimrv] [-f hints_file] [directory | file ...]

DESCRIPTION
     ldconfig utility is used to configure the set of paths used by the
     dynamic linker ld-elf.so.1(1) when searching for shared libraries.  The
     dynamic linker looks for libraries in a set of built-in system
     directories and any directories specified in the hints file.  This
     obviates the need for storing search paths within the executable, see the
     -rpath option for the static linker ld(1).

     The hints file is maintained by ldconfig.  The directories list to be
     stored in the hints file is supplied on the command line.

     Alternatively to the directories list on the command line, files may be
     specified; these are expected to contain directories to scan for shared
     libraries.  Each directory's pathname must start on a new line.  Blank
     lines and lines starting with the comment character `#' are ignored.

     For security reasons, directories which are world or group-writable or
     which are not owned by root produce warning messages and are skipped,
     unless the -i option is present.

     The LD_LIBRARY_PATH environment variable can be used to specify
     additional shared library search directories.  LD_LIBRARY_PATH is a `:'
     separated list of directory paths which are searched by the dynamic
     linker when it needs to load a shared library.  It can be viewed as the
     run-time equivalent of the -L switch of ld(1).

     The following options are recognized by ldconfig:

     -32     Generate the hints for 32-bit ABI shared libraries on 64-bit
             systems that support running 32-bit binaries.

     -elf    Ignored for backwards compatibility.

     -R      Appends pathnames on the command line to the directory list from
             the hints file.

             This is the default action when no options are given.

     -f hints_file
             Read and/or update the specified hints file, instead of the
             standard file.  This option is provided primarily for testing.

     -i      Run in insecure mode.  The security checks will not be performed.

     -m      Instead of replacing the list of the directories to search with
             the directories specified on the command line, merge existing
             list with the specified directories, and write the result to the
             hints file.

     -r      List the current list of the directories from the hints file on
             the standard output.  The hints file is not modified.

             Scan and print all libraries found on the directories list.

     -v      Switch on verbose mode.

SECURITY
     Special care must be taken when loading shared libraries into the address
     space of set-user-Id programs.  Whenever such a program is run by any
     user except the owner of the program, the dynamic linker will only load
     shared libraries from paths found in the hints file.  In particular, the
     LD_LIBRARY_PATH is not used to search for libraries.  Thus, ldconfig
     serves to specify the trusted collection of directories from which shared
     objects can be safely loaded.

FILES
     /var/run/ld-elf.so.hints     Standard hints file for the ELF dynamic
                                  linker.
     /etc/ld-elf.so.conf          Conventional configuration file containing
                                  directory names for invocations with -elf.
     /var/run/ld-elf32.so.hints   Conventional configuration files containing
                                  directory names for invocations with -32.

SEE ALSO
     ld(1), ld-elf.so.1, link(5)

HISTORY
     A ldconfig utility first appeared in SunOS 4.0, it appeared in its
     current form in FreeBSD 1.1.

     The name 'hints file' is historic from the times when the file also
     contained hints to the dynamic linker.  This functionality is not
     provided for ELF.

FreeBSD 13.1-RELEASE-p6          May 15, 2021          FreeBSD 13.1-RELEASE-p6