C++ Primer Plus

Static Duration Variables

C++, like C, provides static storage duration variables with three kinds of linkage: external linkage (accessible across files), internal linkage (accessible to functions within a single file), and no linkage (accessible to just one function or to one block within a function). All three last for the duration of the program; they are less ephemeral than automatic variables. Because the number of static variables doesn’t change as the program runs, the program doesn’t need a special device such as a stack to manage them. Instead, the compiler allocates a fixed block of memory to hold all the static variables, and those variables stay present as long as the program executes. Also if you don’t explicitly initialize a static ...