use of static keyword in c or c++

Question

This is a general C or C++ code related question. Why would you need the static keyword for a global variable in C or C++ if it is already global throughout the program and if this program is only using one file.

Remy Lebeau · Accepted Answer · 2022-05-16 21:59:20Z

4

A global variable has external linkage by default. Meaning, it can be accessed by other translation units by using extern.

Declaring a global variable as static gives it internal linkage. Meaning, it can only be accessed within the translation unit that it is declared in, extern can't reach it.

If the program only has 1 translation unit (.c/.cpp file), declaring a global variable in that unit as static doesn't make any difference. But, if you have multiple translation units, it starts to make more sense to declare globals as static when you don't want to share them across translation units.

See https://en.cppreference.com/w/c/language/storage_duration for more details.

edited May 16, 2022 at 21:59

answered May 15, 2022 at 19:01

Remy Lebeau

609k36 gold badges516 silver badges875 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

John Keubler Over a year ago

I see, most of my programs are using only 1 .cpp file, along with .hpp header files as needed so I don't need the static keyword for global variables for now.

Collectives™ on Stack Overflow

use of static keyword in c or c++

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related