proc file system implementation

Hi Everyone,
Could anybody guide me about how exactly the proc file system is updated.. the interfaces ( the kernel functions ) called for updating proc file system etc..

Proc file systems is known as runtime/virtual filesystem, the files are created by modules and are varied accordingly.

# cat /proc/interrupts

check this again after 2 minus the same command gives you different values

here arew some functions for proc filesystem

struct proc_dir_entry *sample;
create_proc_entry();
remove_proc_entry()