c++ - using global array inside threads -

what want is, if data in array buff inside thread changes, global variable global_buff data must change

#include <process.h> .........  char global_buff_1[50]; char global_buff_2[50];  void thread (int x) {    char buff[50] = {0};    if (x == 0)       buff = global_buff_1;      //this need, how can equal 2 array correctly. want if buff array data changing global_buff changing.    else       buff = global_buff_2;     .............     //do thing      ............. }  int main(int argc, char* argv []) { ................... int y = 0; _beginthread((void(*)(void*))thread, 0, (void*)y); ..................... } 

any helping!

void thread (int x) {    char* buff = 0; // change here pointer     if (x == 0)       buff = global_buff_1; // new these assignments work. , when changing buff    else                     // global_buff_1 , global_buff_2 change depending on       buff = global_buff_2; // assignment done here     .............     //do thing      ............. }