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Hi,

this might be a silly question but I really got stuck here.

Suppose I have:

struct A {
int a;
int b;
int c;
};

struct B {
int x;
int y;
struct A z;
}

struct B params[2];

void doSomethingWithParams(struct B* arg)
{
/* Do something with parameters */
}

void main(void)
{
doSomethingWithParams(params[1].&z);
}

The function-call in main does not work. I get an error: expected a
field name

Is this a limitation of the c language? Is it not possible to get the
address of struct in struct? What would be a alternative to this? I
know I could have static variables for z and assign it as a pointer to
params (with struct A* z in B). But this does not hold relevant
information at one point then...

Thanks for your tips and hints!

On Jun 7, 8:48*am, Borealis <listwo...@gmail.com> wrote:
> Hi,
>
> this might be a silly question but I really got stuck here.
>
> Suppose I have:
>
> struct A {
> * int a;
> * int b;
> * int c;
>
> };
>
> struct B {
> * int x;
> * int y;
> * struct A z;
>
> }
>
> struct B params[2];
>
> void doSomethingWithParams(struct B* arg)
> {
> * /* Do something with parameters */
>
> }
>
> void main(void)
> {
> * doSomethingWithParams(params[1].&z);
>

&params[1].z

Is what you're after.

Tom

Tom St Denis <> wrote:
> On Jun 7, 8:48Â*am, Borealis <listwo...@gmail.com> wrote:
> > this might be a silly question but I really got stuck here.
> >
> > Suppose I have:
> >
> > struct A {
> > Â* int a;
> > Â* int b;
> > Â* int c;
> > };
> >
> > struct B {
> > Â* int x;
> > Â* int y;
> > Â* struct A z;
> > }
> >
> > struct B params[2];
> >
> > void doSomethingWithParams(struct B* arg)
> > {
> > Â* /* Do something with parameters */
> >
> > }
> >
> > void main(void)
> > {
> > Â* doSomethingWithParams(params[1].&z);

> &params[1].z

> Is what you're after.

But note that this gives you the address of the struct A within
struct B (and not the address of a struct B), so the doSomething-
WithParams() should have a prototype of

void doSomethingWithParams(struct A* arg);

Regards, Jens
--
\ Jens Thoms Toerring ___
\__________________________ http://toerring.de

On 7 Jun., 14:59, j...@toerring.de (Jens Thoms Toerring) wrote:
> Tom St Denis <t...@iahu.ca> wrote:
>
>
>
> > On Jun 7, 8:48*am, Borealis <listwo...@gmail.com> wrote:
> > > this might be a silly question but I really got stuck here.
>
> > > Suppose I have:
>
> > > struct A {
> > > * int a;
> > > * int b;
> > > * int c;
> > > };
>
> > > struct B {
> > > * int x;
> > > * int y;
> > > * struct A z;
> > > }
>
> > > struct B params[2];
>
> > > void doSomethingWithParams(struct B* arg)
> > > {
> > > * /* Do something with parameters */
>
> > > }
>
> > > void main(void)
> > > {
> > > * doSomethingWithParams(params[1].&z);
> > &params[1].z
> > Is what you're after.
>
> But note that this gives you the address of the struct A within
> struct B (and not the address of a struct B), so the doSomething-
> WithParams() should have a prototype of
>
> void doSomethingWithParams(struct A* arg);
>
> * * * * * * * * * * * * * * * Regards, Jens
> --
> * \ * Jens Thoms Toerring *___ * * *j...@toerring.de
> * *\__________________________ * * *http://toerring.de


That's right, yes. Typo... Thanks for bringing me back on track!