ld.so(8)						      System Manager's Manual							  ld.so(8)

NAME

       ld.so, ld-linux.so* - dynamic linker/loader

DESCRIPTION

       ld.so  loads  the shared libraries needed by a program, prepares the program to run, and then runs it.  Unless explicitly specified via the
       -static option to ld during compilation, all Linux programs are incomplete and require further linking at run time.

       The necessary shared libraries needed by the program are searched for in the following order

       o      Using the DT_RPATH dynamic section attribute of the binary if present and DT_RUNPATH attribute does not exist.

       o      Using the environment variable LD_LIBRARY_PATH .	Except if the executable is a setuid/setgid binary, in which case it is ignored.

       o      Using the DT_RUNPATH dynamic section attribute of the binary if present.

       o      From the cache file /etc/ld.so.cache which contains a compiled list of candidate libraries previously found in the augmented library
	      path. If, however, the binary was linked with -z nodeflib linker option, libraries in the default library paths are skipped.

       o      In the default path /lib, and then /usr/lib.  If the binary was linked with -z nodeflib linker option, this step is skipped.

SYNOPSIS

       The  dynamic  linker can be run either indirectly through running some dynamically linked program or library (in which case no command line
       options to the dynamic linker can be passed and the dynamic linker which is stored in the .interp section of the program  is  executed)	or
       directly by running:

       /lib/ld-linux.so.*  [OPTIONS] [PROGRAM [ARGUMENTS]]

COMMAND LINE OPTIONS

       --list List all dependencies and how they are resolved.

       --verify
	      Verify that program is dynamically linked and this dynamic linker can handle it.

       --library-path PATH
	      Override LD_LIBRARY_PATH environment variable setting (see below).

       --ignore-rpath LIST
	      Ignore RPATH and RUNPATH information in object names in LIST.

ENVIRONMENT

       LD_LIBRARY_PATH
	      A colon-separated list of directories in which to search for ELF libraries at execution-time.  Similar to the PATH environment vari-
	      able.

       LD_PRELOAD
	      A whitespace-separated list of additional, user-specified, ELF shared libraries to be loaded before all others.  This can be used to
	      selectively  override  functions	in  other shared libraries.  For setuid/setgid ELF binaries, only libraries in the standard search
	      directories that are also setuid will be loaded.

       LD_TRACE_LOADED_OBJECTS
	      If set to non-empty string, causes the program to list its dynamic library dependencies, as if run by ldd, instead of  running  nor-
	      mally.

       LD_BIND_NOW
	      If  set  to non-empty string, causes the dynamic linker to resolve all symbols at program startup instead of deferring function call
	      resolval to the point when they are first referenced.

       LD_WARN
	      If set to non-empty string, warn about unresolved symbols.

       LD_DEBUG
	      Output verbose debugging information about the dynamic linker.  If set to all prints all debugging information it  has,  if  set	to
	      help prints a help message about which categories can be specified in this environment variable.

       LD_DEBUG_OUTPUT
	      File where LD_DEBUG output should be fed into, default is standard output. LD_DEBUG_OUTPUT is ignored for setuid/setgid binaries.

       LD_VERBOSE
	      If  set  to  non-empty string, output symbol versioning information about the program if querying information about the program (ie.
	      either LD_TRACE_LOADED_OBJECTS has been set, or --list or --verify options have been given to the dynamic linker).

FILES

       /lib/ld-linux.so.*  ELF dynamic linker/loader
       /etc/ld.so.cache
	      File containing a compiled list of directories in which to search for libraries and an ordered list of candidate libraries.
       /etc/ld.so.preload
	      File containing a whitespace separated list of ELF shared libraries to be loaded before the program.  libraries and an ordered  list
	      of candidate libraries.
       lib*.so*
	      shared libraries

SEE ALSO

       ldd(1), ldconfig(8).

AUTHORS

       Roland McGrath, Ulrich Drepper and others.  This man page is derived from libc 5 ld.so manual page.

								  30 October 2000							  ld.so(8)