pointers to struct, can't get the hang of it....

[msshapira]

hi,
i'm trying to understand the use of pointer to structs, calling by address, etc.
can get the declarations right:

month* AddMonth(month *monthPtr,month **lastMonth,char[MONTHCODE] name)
{
	//allocate month in mem
	monthPtr=(month*)realloc(month,sizeof(month));
	//check
	CheckAlloc((void*)*monthPtr);
	//move last month pointer
	(*lastMonth)++;
	//add new month name to newly created month
	MyStrcpy((*lastMonth)->name,name);
	return monthPtr;
}

the declaration of this function and the structs:

month* AddMonth(month *monthPtr,month **lastMonth,char[MONTHCODE] name);
typedef struct {
	int dayNum;
	int numOfTasks;
	char *task;
} day;
typedef struct {
	char name[3];
	day *dayInMonth;
} month;

the compiler is saying things like: syntax error : missing '{' before '*'

not sure what i've done wrong
HELP!
thanks

[Elysia]

month* AddMonth(month *monthPtr,month **lastMonth,char[MONTHCODE] name);

Should be:

month* AddMonth(month* monthPtr, month** lastMonth, char name[MONTHCODE]);

Also, I'm not so sure this is a good idea:

CheckAlloc((void*)*monthPtr);

You cast a non-pointer value to a void* pointer.
Furthermore, if the CheckAlloc is supposed to check the pointer, why are you dereferencing it?
If it checks if it's a valid month or so, then why is it taking a void* pointer?
That function is ambiguous to me.

[msshapira]

the way i see it, the code you wrote and the one i wrote are the same thing:
int* pointer, is the same as int *pointer

CheckAlloc((void*)*monthPtr); checks the allocation is successful, this function is to be used with all types of pointer and therefore needs casting... (am i wrong?)

[Elysia]

Nope, it's not the same. Check the last one - the name char array. The size comes after the name.
If it works with pointers, then why do you dereference the pointer before passing it? That makes it a pointer no longer.
And how the compiler is supposed to pass a struct as a void* pointer is beyond me, frankly.

[msshapira]

either way, it's not working.
any idea?
error is in the declarations

[Elysia]

typedef struct
{
	int dayNum;
	int numOfTasks;
	char* task;
} day;

typedef struct
{
	char name[3];
	day* dayInMonth;
} month;

month* AddMonth(month* monthPtr, month** lastMonth, char name[MONTHCODE]);

How about this then?

[msshapira]

thanks... how low can i stoop