Yolinux.com

ldconfig manpage

Search topic Section


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 ] direc-
       tory ...
       /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 libs (i.e., libc5 or
       libc6/glibc) based on what C libs,  if  any,  the  library  was	linked
       against.

       Some  existing  libs  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  libs	 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     Only process 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 4.04 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
       http://www.kernel.org/doc/man-pages/.



GNU				  2015-03-29			   LDCONFIG(8)