Global variables in C ++

Question

In a multi-threaded C ++ application with many classes, I'm trying to figure out which methods define a global variable

• C, define it as global in any source file, define it as extern in the header, which is included in the classes that access this variable.

• Write a Singleton class that contains these global variables and provides set / get methods for writing to a variable.

In the second method, you can manage multi-threaded access through locks in a centralized manner, rather than the first approach.

Are there any better ways?

Answer 1

" " ( - ?), . (, , ), get/put accessors.

Answer 2

. (, cin, cout cerr), , , ( ) .

Answer 3

Singleton. "" .

Answer 4

( ?), , . - , .

Answer 5

.

++ ::, .

:: variable-name;

vriable.

Answer 6

, , , , .

-, , , . . , .

-, , . , . , , .

, .

Answer 7

.

C , Singleton:: instance(). Singleton:: instance() .

, C-, Schwarz Counter. http://en.wikibooks.org/wiki/More_C%2B%2B_Idioms/Nifty_Counter

Answer 8

, handle/body.

" ++" singleton MT .

Answer 9

Not kicking a dead horse, but, as already mentioned, avoiding globals is the best solution. Some reasons are listed here . If a global variable is required, you can consider providing a function for its access to avoid the so-called "global initialization fiasco."