Question from C faq in comp.lang.c

[Shastri]

Hi all,

Can I get a clear idea of what designated initializers in the below
question mean??
Also is it applicable for structures too??


Can I initialize unions?
A: In the original ANSI C, only the first-named member; in C99,
using "designated initializers", yes, any member.


Thanks
Shastri

 

[Mark McIntyre]

Hi all,

Can I get a clear idea of what designated initializers in the below
question mean??
Also is it applicable for structures too??


Can I initialize unions?
A: In the original ANSI C, only the first-named member; in C99,
using "designated initializers", yes, any member.

struct foo{
int x;
double y;
char* z;
}

struct foo = { .x=1; .z="boo";};

Mark McIntyre

 

[Chris Torek]

On 1 Feb 2006 15:18:16 -0800, in comp.lang.c , "Shastri"

Can I get a clear idea of what "designated initializers" [are]?

struct foo{
int x;
double y;
char* z;
}

struct foo = { .x=1; .z="boo";};

This syntax is a little bit wrong -- you mean:

struct foo some_var = { .x = 1, .z = "boo" };

It might also be worth including an array example, and/or a union:

union u {
int i;
double d;
} a[5] = {
[4].d = 3.141592653589793238462643383279502884,
[0].i = 42,
/* the rest will have .i initialized to 0 */
};