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LDD(1)			   Linux Programmer's Manual			LDD(1)



NAME
       ldd - print shared object dependencies

SYNOPSIS
       ldd [option]... file...

DESCRIPTION
       ldd  prints the shared objects (shared libraries) required by each pro-
       gram or shared object specified on the command line.  An example of its
       use and output is the following:


       $ ldd /bin/ls
	       linux-vdso.so.1 (0x00007ffcc3563000)
	       libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e5459000)
	       libcap.so.2 => /lib64/libcap.so.2 (0x00007f87e5254000)
	       libc.so.6 => /lib64/libc.so.6 (0x00007f87e4e92000)
	       libpcre.so.1 => /lib64/libpcre.so.1 (0x00007f87e4c22000)
	       libdl.so.2 => /lib64/libdl.so.2 (0x00007f87e4a1e000)
	       /lib64/ld-linux-x86-64.so.2 (0x00005574bf12e000)
	       libattr.so.1 => /lib64/libattr.so.1 (0x00007f87e4817000)
	       libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f87e45fa000)

       In  the	usual  case,  ldd  invokes  the	 standard  dynamic linker (see
       ld.so(8)) with the LD_TRACE_LOADED_OBJECTS environment variable set  to
       1.   This  causes  the  dynamic linker to inspect the program's dynamic
       dependencies, and find (according to the rules described	 in  ld.so(8))
       and  load the objects that satisfy those dependencies.  For each depen-
       dency, ldd displays the location of the matching object and the	(hexa-
       decimal)	 address  at which it is loaded.  (The linux-vdso and ld-linux
       shared dependencies are special; see vdso(7) and ld.so(8).)

   Security
       Be aware that in some circumstances (e.g., where the program  specifies
       an  ELF	interpreter  other than ld-linux.so), some versions of ldd may
       attempt to obtain the dependency information by attempting to  directly
       execute	the  program (which may lead to the execution of whatever code
       is defined in the program's ELF interpreter, and perhaps	 to  execution
       of  the	program	 itself).   Thus,  you	should	never employ ldd on an
       untrusted executable, since this may result in the execution  of	 arbi-
       trary  code.   A safer alternative when dealing with untrusted executa-
       bles is:

	   $ objdump -p /path/to/program | grep NEEDED

OPTIONS
       --version
	      Print the version number of ldd.

       -v, --verbose
	      Print all information, including, for example, symbol versioning
	      information.

       -u, --unused
	      Print unused direct dependencies.	 (Since glibc 2.3.4.)

       -d, --data-relocs
	      Perform relocations and report any missing objects (ELF only).

       -r, --function-relocs
	      Perform  relocations  for	 both  data objects and functions, and
	      report any missing objects or functions (ELF only).

       --help Usage information.

BUGS
       ldd does not work on a.out shared libraries.

       ldd does not work with some extremely old  a.out	 programs  which  were
       built  before  ldd  support was added to the compiler releases.	If you
       use ldd on one of these programs, the program will attempt to run  with
       argc = 0 and the results will be unpredictable.

SEE ALSO
       pldd(1), sprof(1), ld.so(8), ldconfig(8)

COLOPHON
       This  page  is  part of release 4.10 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/.



				  2016-07-17				LDD(1)