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】
