ldd - print shared object dependencies


   ldd [option]... file...


   ldd  prints  the  shared  objects  (shared  libraries) required by each
   program 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
   dependency, ldd displays the location of the matching  object  and  the
   (hexadecimal)  address  at which it is loaded.  (The linux-vdso and ld-
   linux shared dependencies are special; see vdso(7) and ld.so(8).)

   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
   arbitrary  code.   A  safer  alternative  when  dealing  with untrusted
   executables is:

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


          Print the version number of ldd.

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

   -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.


   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.


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


   This  page  is  part of release 4.09 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

                              2016-07-17                            LDD(1)


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