【Linux】ubuntu下，使用ldconfig解决：error while loading shared libraries: libpcap.so.1: cannot open shared object file: No such file or directory

一、问题描述
编写一个与libpcap有关的程序：test_libpcap.cpp，编译test_libpcap.o成功。

注：之前已经成功安装libpcap，libpcap.so.1.5.3的路径是：/home/test/work/lib；
test_libpcap.cpp的路径是/home/test/work/test_libpcap。

运行test_libpcap.o出现以下提示：

test_libpcap.o: error while loading shared libraries: libpcap.so.1.5.3: cannot open shared object file: No such file or directory

 

二、问题解决
注：以下操作均需要root权限
1.定位“libpcap.so.1.5.3”的路径

# locate libpcap.so.1.5.3
/home/test/work/lib/libpcap.so.1.5.3
/usr/lib/i386-linux-gnu/libpcap.so.1.5.3
/usr/local/lib/libpcap.so.1.5.3

2.将上述路径中的“/home/test/work/lib/libpcap.so.1.5.3”加入“/etc/ld.so.conf.d”中

# cd /etc/ld.so.conf.d
# ls
i686-linux-gnu.conf libc.conf
# echo "# libpcap default configuration" >> libpcap.conf
# echo "/home/test/work/lib/libpcap.so.1.5.3" >> libpcap.conf

3.运行ldconfig命令

# /sbin/ldconfig

4.再次运行test_libpcap.o，成功。

 

三、参考信息

1.man locate

locate(1)                   General Commands Manual                  locate(1)



NAME
       locate - find files by name


SYNOPSIS
       locate [OPTION]... PATTERN...


DESCRIPTION
       locate  reads  one or more databases prepared by updatedb(8) and writes
       file names matching at least one of the PATTERNs  to  standard  output,
       one per line.

       If  --regex is not specified, PATTERNs can contain globbing characters.
       If any PATTERN contains no globbing characters, locate  behaves  as  if
       the pattern were *PATTERN*.

       By default, locate does not check whether files found in database still
       exist (but it does require all parent directories to exist if the data‐
       base  was built with --require-visibility no).  locate can never report
       files created after the most recent update of the relevant database.


EXIT STATUS
       locate exits with status 0 if any match was  found  or  if  locate  was
       invoked  with  one  of the --limit 0, --help, --statistics or --version
       options.  If no match was found  or  a  fatal  error  was  encountered,
       locate exits with status 1.

       Errors  encountered while reading a database are not fatal, search con‐
       tinues in other specified databases, if any.


OPTIONS
       -A, --all
              Print only entries that match all PATTERNs instead of  requiring
              only one of them to match.


       -b, --basename
              Match  only  the base name against the specified patterns.  This
              is the opposite of --wholename.


       -c, --count
              Instead of writing file names on standard output, write the num‐
              ber of matching entries only.


       -d, --database DBPATH
              Replace  the  default database with DBPATH.  DBPATH is a :-sepa‐
              rated list of database file names.  If more than one  --database
              option  is  specified,  the resulting path is a concatenation of
              the separate paths.

              An empty database file name is replaced by the default database.
              A  database file name - refers to the standard input.  Note that
              a database can be read from the standard input only once.


       -e, --existing
              Print only entries that refer to  files  existing  at  the  time
              locate is run.


       -L, --follow
              When  checking  whether files exist (if the --existing option is
              specified), follow trailing symbolic links.  This causes  broken
              symbolic links to be omitted from the output.

              This  is  the  default  behavior.  The opposite can be specified
              using --nofollow.


       -h, --help
              Write a summary of the available options to standard output  and
              exit successfully.


       -i, --ignore-case
              Ignore case distinctions when matching patterns.


       -l, --limit, -n LIMIT
              Exit  successfully  after finding LIMIT entries.  If the --count
              option is specified, the resulting  count  is  also  limited  to
              LIMIT.


       -m, --mmap
              Ignored, for compatibility with BSD and GNU locate.


       -P, --nofollow, -H
              When  checking  whether files exist (if the --existing option is
              specified), do not follow trailing symbolic links.  This  causes
              broken symbolic links to be reported like other files.

              This is the opposite of --follow.


       -0, --null
              Separate  the  entries  on  output using the ASCII NUL character
              instead of writing each entry on a separate line.   This  option
              is  designed  for interoperability with the --null option of GNU
              xargs(1).


       -S, --statistics
              Write statistics about each read  database  to  standard  output
              instead of searching for files and exit successfully.


       -q, --quiet
              Write  no  messages  about  errors encountered while reading and
              processing databases.


       -r, --regexp REGEXP
              Search for a basic regexp REGEXP.  No PATTERNs  are  allowed  if
              this  option  is used, but this option can be specified multiple
              times.


       --regex
              Interpret all PATTERNs as extended regexps.


       -s, --stdio
              Ignored, for compatibility with BSD and GNU locate.


       -V, --version
              Write information about the version and  license  of  locate  on
              standard output and exit successfully.


       -w, --wholename
              Match only the whole path name against the specified patterns.

              This  is  the  default  behavior.  The opposite can be specified
              using --basename.


EXAMPLES
       To search for a file named exactly NAME (not *NAME*), use
              locate -b '\NAME'
       Because \ is a globbing character, this disables the implicit  replace‐
       ment of NAME by *NAME*.


FILES
       /var/lib/mlocate/mlocate.db
              The database searched by default.


ENVIRONMENT
       LOCATE_PATH
              Path  to  additional databases, added after the default database
              or the databases specified using the --database option.


NOTES
       The order in which the requested databases are  processed  is  unspeci‐
       fied,  which  allows  locate  to reorder the database path for security
       reasons.

       locate attempts to be compatible to slocate (without the  options  used
       for  creating  databases)  and  GNU locate, in that order.  This is the
       reason for the impractical default --follow option and for the  confus‐
       ing set of --regex and --regexp options.

       The  short  spelling  of  the  -r option is incompatible to GNU locate,
       where it corresponds to the --regex option.  Use the long option  names
       to avoid confusion.

       The  LOCATE_PATH  environment variable replaces the default database in
       BSD and GNU locate, but it is added to other databases in  this  imple‐
       mentation and slocate.


AUTHOR
       Miloslav Trmac <mitr@redhat.com>


SEE ALSO
       updatedb(8)



mlocate                            Sep 2012                          locate(1)

2.man ldconfig

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).  The cache is used by the run-time linker, ld.so or ld-
       linux.so.  ldconfig 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
       -v     Verbose  mode.   Print  current version number, the name of each
              directory as it is scanned, and  any  links  that  are  created.
              Overrides quiet mode.

       -n     Only  process  directories specified on the command line.  Don't
              process the trusted directories (/lib and  /usr/lib)  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.

       -X     Don't update links.  Unless -N is also specified, the  cache  is
              still rebuilt.

       -f conf
              Use conf instead of /etc/ld.so.conf.

       -C cache
              Use cache instead of /etc/ld.so.cache.

       -r root
              Change to and use root as the root directory.

       -l     Library mode.  Manually link individual libraries.  Intended for
              use by experts only.

       -p     Print the lists of directories and candidate libraries stored in
              the current cache.

FILES
       /lib/ld.so          run-time linker/loader
       /etc/ld.so.conf     File  containing  a list of colon, space, tab, new‐
                           line, or comma-separated directories  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 /lib and /usr/lib.

SEE ALSO
       ldd(1), ld.so(8)

COLOPHON
       This  page  is  part of release 3.54 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



GNU                               2012-05-10                       LDCONFIG(8)

 

四、原文网址[原文发布于2014-09-20 09:56]

 http://www.cnblogs.com/tom-and-jerry/p/3978092.html

 

【完结】