Georg Bauhaus <[EMAIL PROTECTED]> writes:
| Joe Buck wrote:
|
| > Are you using "volatile" correctly? There are situations where "volatile"
| > alone does not suffice and you need more locking, but the Linux and BSD
| > kernel folks manage to optimize their device driver code.
|
| We have just been discussing a similar topic in a de.* newsgroup.
| A busy-loop function is used to effect a delay, not too precise,
| but portably. Like
|
| #define COUNT 1000
|
| void f() {
| /*volatile*/ /*register*/ int i;
|
| for (i = 0; i < COUNT; ++i)
| ;
This must be an FAQ. The above is no way of (no matter how popular
the urban legend makes it) implementing delay. Adding a #pragma just
makes teh situation worse.
-- Gaby
