time

hi
i want channge this code php languge
setInterval("next_page();",4500);

i want run this code

Code:

for($i=0;$i<5000;$i++)
{

fopen("a.txt","r");

// stop (1min) or javascript languages => setInterval("next_page();",8000);
// and run next 1 min 
}  

please help me