How to detect the page read/write fault ?

[Yung-Chang Chiu]

On the x86 machine, i can use the below program to detect read or write fault.
write_fault=uap->uc_mcontext.gregs[REG_ERR]&4;

but it don't work on AMD64 machine.

I have been search on internet, but there is no answer for AMD64.
Anybody can tell me how to do?