存放Pear的目录：

# cd /usr/local/lib

用“phpfi“口令登录:

# cvs -d :pserver:cvsread@cvs.php.net:/repository login

用以下命令得到所有的pear文件，同时也可以用来更新已经下载的文件。其他的参数有："today", "last month",等。我推荐用"last week"参数，因为一般bugs的提交和修改都是每周一次。 

# cvs -d :pserver:cvsread@cvs.php.net:/repository export -D "last week" php4/pear

编辑php.ini文件加上下面一段在include_path处： /usr/local/lib/php4/pear 如果没有修改的权限，可以通过这条语句在代码中实现： ini_set('include_path', 'path_to_pear');

<?php
 // The pear base directory must be in your include_path
 require_once'DB.php';
 $user='foo';
 $pass='bar';
 $host='localhost';
 $db_name='clients_db';
 
 // Data Source Name: This is the universal connection string
 $dsn="mysql://$user:$pass@$host/$db_name";
 
 // DB::connect will return a Pear DB object on success
 // or a Pear DB Error object on error
 // You can also set to TRUE the second param
 // if you want a persistent connection:
 // $db = DB::connect($dsn, true);
 $db=DB::connect($dsn);
 
 // With DB::isError you can differentiate between an error or
 // a valid connection.
 if(DB::isError($db)){
 die($db->getMessage());
 }
 ....
 // You can disconnect from the database with:
 $db->disconnect();
 ?>

*phptype: Database backend used in PHP (mysql, odbc etc.)
 *dbsyntax: Database used with regards to SQL syntax etc.
 *protocol: Communication protocol to use (tcp, unix etc.)
 *hostspec: Host specification (hostname[:port])
 *database: Database to use on the DBMS server
 *username: User name for login
 *password: Password for login
 *
 * The format of the supplied DSN is in its fullest form:
 *
 *phptype(dbsyntax)://username:password@protocol+hostspec/database
 *
 * Most variations are allowed:
 *
 *phptype://username:password@protocol+hostspec:110//usr/db_file.db
 *phptype://username:password@hostspec/database_name
 *phptype://username:password@hostspec
 *phptype://username@hostspec
 *phptype://hostspec/database
 *phptype://hostspec
 *phptype(dbsyntax)
 *phptype

mysql-> MySQL
 pgsql-> PostgreSQL
 ibase-> InterBase
 msql-> Mini SQL
 mssql-> Microsoft SQL Server
 oci8-> Oracle 7/8/8i
 odbc-> ODBC (Open Database Connectivity)
 sybase -> SyBase
 ifx-> Informix
 fbsql-> FrontBase