screen 学习

1.screen -S cheapest(创建cheapest)
2.scrren -ls (查看所有会话)
3.kill -9 会话编号（杀掉进程）
4.screen -wipe 编号（会话列表中清除所有已死掉的会话）

5.screen -r 会话编号（查看会话）
注意：若mysql启动报：

6.退出exit(注意退出后会话进程停止，也就是说服务器不运行)

变为Attached

7.若想把Attached变为Detached，最好运行

screen -d 会话编号则会把（Attached变为Detached）


111128 10:37:57 mysqld_safe mysqld from pid file /root/mpp/program/mysqldata/mysql/bogon.pid ended
111128 10:44:12 mysqld_safe Starting mysqld daemon with databases from /root/mpp/program/mysqldata/mysql
111128 10:44:12 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Table 'plugin' is read only
111128 10:44:12 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
111128 10:44:12 InnoDB: The InnoDB memory heap is disabled
111128 10:44:12 InnoDB: Mutexes and rw_locks use GCC atomic builtins
111128 10:44:12 InnoDB: Compressed tables use zlib 1.2.3
111128 10:44:12 InnoDB: Using Linux native AIO
111128 10:44:12 InnoDB: Initializing buffer pool, size = 128.0M
111128 10:44:12 InnoDB: Completed initialization of buffer pool
111128 10:44:12 InnoDB: highest supported file format is Barracuda.
111128 10:44:12  InnoDB: Waiting for the background threads to start
111128 10:44:13 InnoDB: 1.1.8 started; log sequence number 63970233
111128 10:44:13 [ERROR] Can't start server : Bind on unix socket: Permission denied
111128 10:44:13 [ERROR] Do you already have another mysqld server running on socket: /root/mpp/program/mysqldata/mysql/mysql.sock ?
111128 10:44:13 [ERROR] Aborting

111128 10:44:13  InnoDB: Starting shutdown...
111128 10:44:13  InnoDB: Shutdown completed; log sequence number 63970233
111128 10:44:13 [Note] /usr/sbin/mysqld: Shutdown complete

这样的错误：
首先启动：
bin/mysqld_safe --user=mysql
然后再在
service mysql start若提示又有一个端口启动3306
则重新启动就OK了。