How to stop core file generation in the server from php?

■ Requirement : stop core file generation in the server from php
■ OS Environment : Linux[RHEL, Centos]
■ Application: ulimit
■ Implementation Steps : 

          A core file records memory image of running process.when a php process is killed, apache creates core files under your account.These core files take too much of space on server.There is no harm on deleting these files.You can get rid off these core files by modifying the httpd start up file.

Edit /usr/sbin/httpd and make ulimit like below :

ulimit -c 0