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Designated initializers in C99

In C90, there is no way to initialize specific members of arrays, structures, or unions. C99 supports the initialization of specific members of an array, structure, or union by either name or subscript through the use of designated initializers.

For example:

typedef struct
    char *name;
    int rank;
} data;
data vars[10] = { [0].name = "foo", [0].rank = 1,
                  [1].name = "bar", [1].rank = 2,
                  [2].name = "baz", 
                  [3].name = "gazonk" };

Members of an aggregate that are not explicitly initialized are initialized to zero by default.