What is the Difference between Constant and Volatile in C

Question

what is the difference between Constant and Volatile

and

What is difference Volatile int i =10 And int i =10;

please let me briefly

One is constant and the other is not? Also check e.g. [this reference](http://en.cppreference.com/w/cpp/language/cv). — Some programmer dude, Jan 29 '14 at 07:24
http://stackoverflow.com/questions/5822386/the-volatile-keyword-in-c-language and generally http://en.wikipedia.org/wiki/Volatile_variable — Ozair Kafray, Jan 29 '14 at 07:25
Please search enough before asking questions. Related: [What are the differences between const and volatile pointer in C?](http://stackoverflow.com/questions/2089464/what-are-the-differences-between-const-and-volatile-pointer-in-c?lq=1) — legends2k, Jan 29 '14 at 07:25
you should specify the version of the language that you are targeting/using — user2485710, Jan 29 '14 at 07:26

score 1 · Answer 1 · answered Jan 29 '14 at 07:27

For a start

int i = 0;

Is not a constant, as it requires the const keyword. A constant cannot be modified and requires to be initialized (you can't put const int i; i = 10;)

Volatile [variables] can be modified externally, for example

asm volatile

Would state the the assembly code can be externally modified

What is the Difference between Constant and Volatile in C

1 Answers1