Hello to all C geeks
My query is as follows
i declare a variable in main as
UINT8 *c[5]
if i check for sizeof(c) it returns 20, i.e 20/4 = 5 elements.
This is fine .
Now i have a function
void func(UINT8 **s,/*other args*/)
and i call this function from main passing c as first argument for s.
Now my problem is that inside the func when i call sizeof(s) it shows 4
i.e the size of one char pointer.
So there is no way for me to know exactly how many elements are there
in the argument.
I have a feeling that it is not possible in C as it dosnt support RTTI
stuff and all but
i will appreciate if anyone can help me or give me some alternative.
thanks in advance & with best regards
shyam 3 5688
shyam wrote: Now i have a function
void func(UINT8 **s,/*other args*/)
and i call this function from main passing c as first argument for s. Now my problem is that inside the func when i call sizeof(s) it shows 4
i.e the size of one char pointer.
So there is no way for me to know exactly how many elements are there in the argument.
No, this was asked here last week, go back and have a look at the
replies on that thread.
--
Ian Collins.
shyam wrote: i declare a variable in main as UINT8 *c[5]
if i check for sizeof(c) it returns 20, i.e 20/4 = 5 elements.
This is fine .
Now i have a function
void func(UINT8 **s,/*other args*/)
and i call this function from main passing c as first argument for s. Now my problem is that inside the func when i call sizeof(s) it shows 4
i.e the size of one char pointer.
So there is no way for me to know exactly how many elements are there in the argument.
no, you'll have to pass it.
I have a feeling that it is not possible in C as it dosnt support RTTI stuff and all but i will appreciate if anyone can help me or give me some alternative.
void func (UINT8 **s, size_t size)
and call it:
int main (void)
{
UINT8 *c[5]
func (&c, sizeof(c) / sizeof(c [0]));
}
--
Nick Keighley
shyam wrote: Hello to all C geeks
My query is as follows
i declare a variable in main as UINT8 *c[5]
if i check for sizeof(c) it returns 20, i.e 20/4 = 5 elements.
This is fine .
Now i have a function
void func(UINT8 **s,/*other args*/)
and i call this function from main passing c as first argument for s. Now my problem is that inside the func when i call sizeof(s) it shows 4
i.e the size of one char pointer.
Actually, given your declaration it would be the size of a pointer to
pointer to char. So there is no way for me to know exactly how many elements are there in the argument.
I have a feeling that it is not possible in C as it dosnt support RTTI stuff and all but i will appreciate if anyone can help me or give me some alternative.
thanks in advance & with best regards
Basically you're right. There's no way to determine the length of an
array that gets passed to a function as an argument. As others have
pointed out, this question has been asked repeteadly in this newsgroup.
There are a number of ways to work arround this problem, google the
newsgroups a bit and you should find some. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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