Red Hat

[root@server ~]# su - test1
/app/modules/0/bin/modulecmd: error while loading shared libraries: libtcl.so.0: cannot open shared object file: No such file or directory
/app/modules/0/bin/modulecmd: error while loading shared libraries: libtcl.so.0: cannot open shared object file: No such file or directory
server [3:03pm] [/home/test1] -> exit

[root@server ~]# rpm -qa | grep tcl
tcl-8.5.7-6.el6.i686
tcl-devel-8.5.7-6.el6.i686
tcl-8.5.7-6.el6.x86_64

       -rpath=dir
       Add a directory to the runtime library search path.    This is used when linking an ELF
       executable with shared objects.  All -rpath arguments are concatenated and passed to
       the runtime linker, which uses them to locate shared objects at runtime.  The -rpath
       option is also used when locating shared objects which are needed by shared objects
       explicitly included in the link; see the description of the -rpath-link option.  If
       -rpath is not used when linking an ELF executable, the contents of the environment
       variable "LD_RUN_PATH" will be used if it is defined.
 
       The -rpath option may also be used on SunOS.  By default, on SunOS, the linker will
       form a runtime search patch out of all the -L options it is given.  If a -rpath option
       is used, the runtime search path will be formed exclusively using the -rpath options,
       ignoring the -L options.  This can be useful when using gcc, which adds many -L
       options which may be on NFS mounted file systems.
 
       For compatibility with other ELF linkers, if the -R option is followed by a directory
       name, rather than a file name, it is treated as the -rpath option.
 
       -rpath-link=dir
       When using ELF or SunOS, one shared library may require another.  This happens when an
       "ld -shared" link includes a shared library as one of the input files.
 
       When the linker encounters such a dependency when doing a non-shared, non-relocatable
       link, it will automatically try to locate the required shared library and include it
       in the link, if it is not included explicitly.  In such a case, the -rpath-link option
       specifies the first set of directories to search.  The -rpath-link option may specify
       a sequence of directory names either by specifying a list of names separated by
       colons, or by appearing multiple times.
 
       This option should be used with caution as it overrides the search path that may have
       been hard compiled into a shared library. In such a case it is possible to use
       unintentionally a different search path than the runtime linker would do.
 
       The linker uses the following search paths to locate required shared libraries:
 
       1.  Any directories specified by -rpath-link options.
 
       2.  Any directories specified by -rpath options.  The difference between -rpath and
           -rpath-link is that directories specified by -rpath options are included in the
           executable and used at runtime, whereas the -rpath-link option is only effective
           at link time. Searching -rpath in this way is only supported by native linkers and
           cross linkers which have been configured with the --with-sysroot option.
 
       3.  On an ELF system, for native linkers, if the -rpath and -rpath-link options were
           not used, search the contents of the environment variable "LD_RUN_PATH".
 
       4.  On SunOS, if the -rpath option was not used, search any directories specified
           using -L options.
 
       5.  For a native linker, the search the contents of the environment variable
           "LD_LIBRARY_PATH".
 
       6.  For a native ELF linker, the directories in "DT_RUNPATH" or "DT_RPATH" of a shared
           library are searched for shared libraries needed by it. The "DT_RPATH" entries are
           ignored if "DT_RUNPATH" entries exist.
 
       7.  The default directories, normally /lib and /usr/lib.
 
       8.  For a native linker on an ELF system, if the file /etc/ld.so.conf exists, the list
           of directories found in that file.
 
       If the required shared library is not found, the linker will issue a warning and
       continue with the link.