How can I have non-static thread-local variable for each instance

Question

The problem itself:

class B{/*...*/};
class A {
    /* members */
    NON-static thread_local B var; // and a thread_local variable here
            


        

Answer 1

Where available, you could use pthread-functions pthread_getspecific and pthread_setspecific for a getter and a setter for that purpose:

#include 

class A {
private:
#define varKey 100L

public:

    int getVar() {
        void *mem = pthread_getspecific(varKey);
        if(mem)
            return *((int*)mem);
        else
            return 0;
    }

    void setVar(int val) {
        void *mem = malloc(sizeof(int));
        *((int*)mem)=val;
        pthread_setspecific(varKey, mem);
    }

    ~A() {
        void *mem = pthread_getspecific(varKey);
        if (mem)
            free(mem);
    }

};