Dynamically loop through array of structures

[uidzer0]

Hey everyone,

I apologize in advance for this novice question however I'm not having
any luck finding the answer myself.

I'm attempting to loop through an array of structures passed to a
function, however I'm not sure how to obtain the number of elements in
the array.

The structure is defined as:
typedef struct {
time_t creation_date;
int priority;
char *text;
} note;

And here's the function prototype:
void get_notes(note *notes);

How would I dynamically loop through *notes?

[Richard Bos]

Re: Dynamically loop through array of structures

uidzer0 <ben.lemasurier @gmail.comwrote :

I'm attempting to loop through an array of structures passed to a
function, however I'm not sure how to obtain the number of elements in
the array.

You can't. You have to pass that number in to the function, use a
terminator element, or have some other way to find out. This is the same
for all arrays, whether or not they're made of structs.

Richard

[uidzer0]

Re: Dynamically loop through array of structures

On Apr 15, 9:13 am, r...@hoekstra-uitgeverij.nl (Richard Bos) wrote:

uidzer0 <ben.lemasur... @gmail.comwrote :

I'm attempting to loop through an array of structures passed to a
function, however I'm not sure how to obtain the number of elements in
the array.

>
You can't. You have to pass that number in to the function, use a
terminator element, or have some other way to find out. This is the same
for all arrays, whether or not they're made of structs.
>
Richard

Ahh... well that makes more sense - thanks.

[CBFalconer]

Re: Dynamically loop through array of structures

uidzer0 wrote:

>
I'm attempting to loop through an array of structures passed to
a function, however I'm not sure how to obtain the number of
elements in the array.
>
The structure is defined as:
typedef struct {
time_t creation_date;
int priority;
char *text;
} note;
>
And here's the function prototype:
void get_notes(note *notes);
>
How would I dynamically loop through *notes?

One way is to hold the pointers to note (i.e. the note* items) in
an array terminated with a NULL. Then the function might be:

void get_notes(note *notes) {
while (*notes) {
process_one_not e(*notes);
notes++;
}
}

but you would be better advised to get rid of the void and return
an error indicator. Same for process_one_not e()

--
[mail]: Chuck F (cbfalconer at maineline dot net)
[page]: <http://cbfalconer.home .att.net>
Try the download section.


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[David Thompson]

Re: Dynamically loop through array of structures

On Tue, 15 Apr 2008 16:59:26 -0400, CBFalconer <cbfalconer@yah oo.com>
wrote:

uidzer0 wrote:

I'm attempting to loop through an array of structures passed to
a function, however I'm not sure how to obtain the number of
elements in the array.

The structure is defined as:
typedef struct {
time_t creation_date;
int priority;
char *text;
} note;

And here's the function prototype:
void get_notes(note *notes);

How would I dynamically loop through *notes?

>
One way is to hold the pointers to note (i.e. the note* items) in
an array terminated with a NULL. Then the function might be:
>

OP doesn't have an array of pointers, but one pointer to an array.

void get_notes(note *notes) {
while (*notes) {
process_one_not e(*notes);
notes++;
}
}
>

For an array of pointer you need (modulo spacing)
void get_notes (note * * notes)
then as you have it. Or (equivalent to the compiler)
void get_notes (note * notes [] )
to emphasize the array-of-pointer-ness, but downplay the fact that
array parameters/arguments are really pointers; pick your poison.

- formerly david.thompson1 || achar(64) || worldnet.att.ne t