output of struct? confused....

**Soulzityr** · 03-01-2010

The output makes no sense to me, am i recording the info into the struct wrong?

i changed from struct customer makeCustomer to void; the one that returns a customer outputs values just as weird, with no name output, time is 0, and items is a huge number

Code:

struct customer {
   char name[30];
   int items;
   int time;
};

void makeCustomer(struct customer a,char n[30], int i, int t) {
   strcpy(a.name,n);    
   a.items=i;
   a.time=t;
}

int main() {
   struct customer test;
   char b[30];
   b[0]='j';
   b[1]='a';
   b[2]='s';
   int items=5;
   int time=60;
   makeCustomer(test,b,items,time);
   printf("Name: %s--Items: %d--Time: %d\n",test.name,test.items,test.time);
   system("pause"); 
}

OUTPUT: Name: H*b--Items: 236--Time: 4602016

**laserlight** · 03-01-2010

Originally Posted by Soulzityr

The output makes no sense to me, am i recording the info into the struct wrong?

In a way. The problem is that makeCustomer() operates on a copy of the object passed to it. You should pass the address of the object that you wish makeCustomer() to operate on, i.e., a should be a pointer to struct customer (and you should use a name that is more descriptive than a). Of course, you need to change the implementation of the function accordingly.

**Soulzityr** · 03-01-2010

so i have to make everything pointers, including in main????

**laserlight** · 03-01-2010

Originally Posted by Soulzityr

so i have to make everything pointers, including in main?

No. Recall the use of the address-of operator, e.g., &test results in a pointer to test.

**Soulzityr** · 03-01-2010

Code:

void makeCustomer(struct customer &a,char n[30], int i, int t) {
   strcpy(a.name,n);    
   a.items=i;
   a.time=t;
}

Heh my output now works, thanks

ois this what you meant though?

**laserlight** · 03-01-2010

Eh, no. That is the use of a reference parameter in C++, but you are writing a C program. I suggest that you check to make sure that you are compiling as C, otherwise you could get very confused.

**Soulzityr** · 03-01-2010

oh you are right, i had it saved as cpp file, and now youre right, compile says its an error :P

hmm how do i access address for function then with the & or w/e >.<

**laserlight** · 03-01-2010

You should do something like this:

Code:

void makeCustomer(struct customer *a, char n[], int i, int t) {
   strcpy(a->name, n);
   a->items = i;
   a->time = t;
}

**Soulzityr** · 03-01-2010

ugh sorry i never learned this well at all; so i made my method look at yours and i tried various ways of calling it

havnig

struct customer* test2

and then makeCustomer(test2...) crashes the program

struct customer test2; then makeCustomer(test2...) doesnt run cuz of argument error which makes sense

then struct customer test2 and makeCustomer(*test2...) also fails. sorry haha i am not quite sure on how to write the syntax >.<

**laserlight** · 03-01-2010

Recall my previous post about using the address-of operator:

Code:

makeCustomer(&test, b, items, time);

By the way, time is not a good variable name to use since it can conflict with a function named time from <time.h>.

**Soulzityr** · 03-01-2010

ahh hmm i will change it then, thanks

as for what you said before about address-of operators, it sort of passes over my head; im sorry >.< my understanding of it is kinda fuzzy......and what it means in terms of when icall it

EDIT: hmm nvm...i think i got it...going to test the output

**Soulzityr** · 03-01-2010

heheh sorry thanks for helping me with that

it works now

i tried the same thing with my enqueue method but it doesnt work. is it okay if i ask you for help with that? >.<

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