static-variables

Is there a use for flagging a variable as static , when it lies in the global scope of a .cpp file, not in a function? Can you use the static keyword for functions as well? If yes, what is their use? In this case, keyword static means the function or variable can only be used by code in the same cpp file. The associated symbol will not be exported and won't be usable by other modules. This is good practice to avoid name clashing in big software when you know your global functions or variables are not needed in other modules. Nawaz Yes, if you want to declare file-scope variable, then static

This question already has an answer here: Main Program and Shared Library initializes same static variable in __static_initialization_and_destruction_0 1 answer I am working on a project that has a class 'A' that contains a static stl container class. This class is included in both my main program and a .so file. The class uses the default(implicit, not declared) constructor/destructor. The main program loads the .so file using dlopen() and in its destructor, calls dlclose(). The program crashes after main exits when glibc calls the destructor for the static class member variable. The problem

I want to know what actually going under the hood,how compiler treats static variables. Unlike auto variable, static variable's value persist even after the end of block but how compilers actually handle this? Unlike local variables which go on stack, static variables are kept in special data segments. Which segment your static variable goes to depends on if they are 0 initialized or not. 0 initialized static data goes in .BSS (Block Started by Symbol), non 0 initialized data goes in .DATA . If you want to learn more what about different segments within executable files, this Wikipedia entry

So I'm using static class members so I can share data between class methods and static methods of the same class (there will only be 1 instantiation of the class). I understand this fine, but I'm just wondering when the static members get initialized? Is it on import? On the first use of the class? Because I'm going to be calling the static members of this class from more than 1 module (therefore more than 1 import statement). Will all the modules accessing the static methods share the same static data members? And if my main client deletes the instance of my class, and then recreates it

I have a BroadcastReceiver class. I have some static variables declared whose value is updated in side the onReceive() method. As per my knowledge static variable will keep it's value across the onReceive calls. Is there any possibility when I will loose those values(Like my class will be unloaded resetting the static variables)? These are basically some temporary variables I need to be available for multiple onReceive calls. From the documentation for BroadcastReceiver Lifecycle ... A BroadcastReceiver object is only valid for the duration of the call to onReceive(Context, Intent). Once your