Search code examples
cmalloccalloc

Malloc calloc fails to allocate structure

I get null memory using following code of malloc/calloc. Sometimes it fails to allocate memory for "name1" and then strcpy fails. Please guide.

struct testMalloc
{
    char name1[90];
    char name2[90]; 
    struct testMalloc* ptr;
};
int main(int argc, char* argv[])
{
    struct testMalloc* test = 0 ;   
    int size = 0;
    size = sizeof(struct testMalloc);

    printf("Size of struct is %d", size);

    test = (struct testMalloc*) calloc(sizeof(struct testMalloc));  
    
    strcpy((test->name1), "hdshdssdsdfsfffffffffffffffffffffffffffffh");

    return 0;

}
Solution

  • You do not include <stdlib.h> for the compiler to know the signature of calloc and in this case it uses K&R calling convention.

    If you include <stdlib.h> the code won't compile before to correctly call the calloc.