What are `static` functions in C?

Basically, this is yet another meaning of static. When you write static preceding a function declaration, its meaning is “this function is only callable within this translation unit”.

A “translation unit” is the input which corresponds to an object file (foo.o) as output. In C, this is usually a foo.c file. Or more precisely, it’s the output after running the preprocessor on foo.c.

Tagged #semantics, #c, #programming.

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