i have initialized an array using calloc.
i can only pass the pointer to a function.
in the function i need to find the length of the array. how do i do it??
wen i use the sizeof() operator it always gives me the value 4 ?? i dont understnd.
#include <stdio.h>
#include <stdlib.h>
int main() {
double *array;
array = (double *)malloc(10*sizeof(double));
printf("size = %d",sizeof(array));
return 0;
}
Pass the length of the dynamic array as an argument.Originally Posted by slash_axl
Look up a C++ Reference and learn How To Ask Questions The Smart Way
And don't forget to free!
is there any other method other than passing the length as an argument??
Not in C, no. You need to keep track of the length.
You could designate some special value to terminate the array, like how the null character is used for a string. However, there is then the danger of out of bounds access should you forget to actually place that value at the appropriate point in the array. Of course, this cannot be used if there is no suitable value, and then it potentially wastes a little space.
Look up a C++ Reference and learn How To Ask Questions The Smart Way
thanx a lot!!!
And don't forget code tags either.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
Also, no need to cast malloc, if you are using a C compiler.
1. Get rid of gets(). Never ever ever use it again. Replace it with fgets() and use that instead.
2. Get rid of void main and replace it with int main(void) and return 0 at the end of the function.
3. Get rid of conio.h and other antiquated DOS crap headers.
4. Don't cast the return value of malloc, even if you always always always make sure that stdlib.h is included.
Something to keep in mind as well is that you should get into the habit of checking the returned value from malloc(). If it returns NULL, and you dereference that, you run into trouble.Code:#include <stdio.h> #include <stdlib.h> int main() { double *array; array = (double *) malloc(10 * sizeof(double)); printf("size = %d", sizeof(array)); return 0; }
As for what claudiu wrote [above] about casting malloc(), here are some links from FAQs:
- Casting Malloc
- C-FAQ - 7.7
- C-FAQ - 7.7b
