L
lak
what is "volatile"? what is the use of this?
P
Porkling
It means "let me be".
It tells compiler donot optimize me because of I would change in
runtime.
J
jaysome
Search the following web site for "volatile" and read all of the
articles in the search results.
http://www.embedded.com/
After reading these articles, if you still have questions, then by all
means ask them here.
Best regards
K
karthikbalaguru
"volatile" is a 'qualifier' that is used at the time of
declaration. It tells the compiler that the value of the
variable may change at any time-without being manipulated from
your code. For example , registers(Status Registers) whose
values may change asynchronously at any point of time from
external factors . Also, it is very useful in ISRs and
Multithreaded programming.
It is very common in Embedded to declare status register as
volatile. It implies that it can be changed by external
hardware at any point of time during the lifetime of the
program and the compiler must not optimise it if it is not
used in the current program.It is for optimisation .
There are lot of good articles regarding 'volatile' in
internet. Try googling.
S
santosh
lak said:
It indicates to the compiler that the object so qualified should not be
subject to optimisation, particularly that it can be modified
asynchronously from outside the program. Typically this means that
reading the object, actually accesses it, and not some compiler cached
copy, even if the compiler believes that the object has not changed. It
will also prevent the compiler from keeping the object entirely in a
register, even if the object's lifetime is small.