auto


declares an automatic variable


        Management type and size variables are automatic, no statement is, in principle, necessary. Their visibility and permanence can be:
Automatic (no statement)
        It is known that within the function where it is defined (without declaration), and it is lost output.

See also:

static

Statement:
static x;
        It is known that within the function where it is defined and retains its value.

externe

Statement:
extern x;
        It is known wherever it is so declared.

globale

Statement:
globale x;
        It is known in all program functions defined on an object and unknown to the outside.