Question

Both Static and Global variables in C are stored in Data segment ( Uninitialized or Initialized ) but Static variable scope is only that file or that function and global variable scope is whole program and both variables life is whole program how it is implemented. They are stored in same segment even though how they different in behavior.

Answer 1

Even both are in the data segement there is a difference ,static variables has internal linkage and global has external linkage (by default) that’s why static is visible in the current translation unit but globals are visible in others.

By declaring variables static (which are in global scope), It means you are restricting the variable to the current file only.

Also initialzed and uninitialized variables are stroed in two different segement

here is the actual segmentation for every variables and code for a program.

C99 Standard : 6.2.2 Linkages of identifiers

2

In the set of translation units and libraries that constitutes an entire program, each
declaration of a particular identifier with external linkage denotes the same object or
function. Within one translation unit, each declaration of an identifier with internal
linkage denotes the same object or function. Each declaration of an identifier with no
linkage denotes a unique entity.

3

If the declaration of a file scope identifier for an object or a function contains the storageclass
specifier static, the identifier has internal linkage.22)