Thank u all for ur responses ..
I have one more problem in the crons. The problem is that after making the application accessed through https only the crons are now no more called. So can anyone tell that is there anything to be changed now incase https is used instead of http.
The way I was calling previously :
* * * * * /usr/bin/lynx --dump http://localhost/cron_test.php
Now I am trying with
* * * * * /usr/bin/lynx --dump https://localhost/cron_test.php
but still the script is not called