how getch()?

[Ratheesh Kumar]

My doubt is on the working of getch() function based on the following observations
1) if the pressed key has an ascii code,only that can be read using a single call to getch()
2) if the key has not an ascii code then the first call to getch() returns a zero and ,if we made a second call, it will return the scan code with out an additional key press.
Some one please help me to understand getch()

[suresh_punniyakkodi]

Hellow Rathish Kumar,
Please follow the following,
Alphabets, Numbers are have ascii value and scan value. But, Arrow keys, Ctrl, Shift, Function Keys are have only scan value.

For Example,
int a;
a = getch();
if(a == 0)
a = getch();

If you press numbers or alphabets, then ascii values is stored in the variable a.
But you pressed esc or enter or arrow keys, then that keys are not have ascii value(only scan value). so, system will automatically gets scan value and stored it in to the variable a(With out using another time reading input from user).

Regards,
Suresh