在“mysql”管理的pid文件退出没有更新文件

I am in a serious problem while installing mysql on ubuntu 12.04 32 bit. when i start mysql with command ''./mysql.server start'' I got this error Manager of pid file quit without updating pid file. I installed ''mysql-5.1.39-linux-i686-glibc23''. I thoroughly search for the solution to fix this error but cannot resolve it yet. I copied my-medium.cnf file to the /etc directory and rename it by my.cnf also edited this file in the section ''The mysql Server'' and add these lines ''datadir = /exports/disk0/data'' but could fix this problem. Can any one help on this.I am in a serious problem while installing mysq