我无法从PHP连接到远程oracle数据库。我一直在网上关注说明，当我尝试安装oci8时，我收到以下错误（最后3行）：
sudo pecl install oci8-1.3.4.tgz
[sudo] password for denny:
downloading oci8-1.3.4.tgz ...
Starting to download oci8-1.3.4.tgz (134,240 bytes)
.............................done: 134,240 bytes
10 source files, building
running: phpize
Configuring for:
PHP Api Version: 20121113
Zend Module Api No: 20121212
Zend Extension Api No: 220121212
Please provide the path to the ORACLE_HOME directory. Use 'instantclient,/path/to/instant/client/lib' if you're compiling with Oracle Instant Client [autodetect] : /opt/oracle/instantclient
building in /tmp/pear/temp/pear-build-rootGYzIDo/oci8-1.3.4
running: /tmp/pear/temp/oci8/configure --with-oci8=/opt/oracle/instantclient
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for a sed that does not truncate output... /bin/sed
checking for cc... cc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables...
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether cc accepts -g... yes
checking for cc option to accept ISO C89... none needed
checking how to run the C preprocessor... cc -E
checking for icc... no
checking for suncc... no
checking whether cc understands -c and -o together... yes
checking for system library directory... lib
checking if compiler supports -R... no
checking if compiler supports -Wl,-rpath,... yes
checking build system type... x86_64-unknown-linux-gnu
checking host system type... x86_64-unknown-linux-gnu
checking target system type... x86_64-unknown-linux-gnu
checking for PHP prefix... /usr
checking for PHP includes... -I/usr/include/php5 -I/usr/include/php5/main -I/usr/include/php5/TSRM -I/usr/include/php5/Zend -I/usr/include/php5/ext -I/usr/include/php5/ext/date/lib
checking for PHP extension directory... /usr/lib/php5/20121212
checking for PHP installed headers prefix... /usr/include/php5
checking if debug is enabled... no
checking if zts is enabled... no
checking for re2c... no
configure: WARNING: You will need re2c 0.13.4 or later if you want to regenerate PHP parsers.
checking for gawk... gawk
checking for Oracle (OCI8) support... yes, shared
checking PHP version... 5.5.9, ok
checking Oracle Install Directory... /opt/oracle/instantclient
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking size of long int... 8
checking if we're on a 64-bit platform... yes
checking OCI8 libraries dir... configure: error: Oracle (OCI8) required libraries not found
ERROR: `/tmp/pear/temp/oci8/configure --with-oci8=/opt/oracle/instantclient' failed
我从oracle网站（http://www.oracle.com/technetwork/database/features/instant-client/index-097480.html）下载了oracle instantclient，用于linux 64位，并在文件夹/ opt / oracle中解压缩。一些帮助将不胜感激。