I'm trying to malloc an array inside a struct but I keep getting segmentation errors when I run the program.
The compares function is just something I'm testing so it shouldn't be a part of the problem
typedef struct {
char *string;
} prod_t;
int
main(int agrc, char **argv){
int i = 0;
prod_t *c = NULL;
char str2[100] = "abcd";
c->string = (char *) malloc( 5 * sizeof(char));
strcpy(c->string,str2);
compares(c->stock,str2,i);
return 0;
}
The problem is that you're allocating space for the string, but you're not allocating the struct at all. c remains set to NULL and you're trying to dereference it.
Allocate space for the struct before assigning to its members
prod_t *c = malloc(sizeof(prod_t));
And, as a sidenote for your next-to-fix error: this field doesn't exist
c->stock
You need to allocate space for the struct before you can assign to the string member:
prod_t *c = malloc(sizeof(prod_t));
Also see Do I cast the result of malloc?
First of all, don't cast result of malloc. You only need to do that in C++. In C, it can actually hide potential problems.
Second of all, you need to allocate (or statically declare) your structure.
Third, c->stock doesn't exist. You probably meant c->string.
typedef struct {
char *string;
} prod_t;
int
main(int agrc, char **argv) {
int i = 0;
prod_t *c = malloc( sizeof( prod_t ));
char str2[100] = "abcd";
c->string = malloc( 5 * sizeof(char));
strcpy(c->string,str2);
compares(c->string,str2,i);
return 0;
}
prod_t *c.c = malloc(sizeof *c);, thenc->string = malloc(5 * sizeof *(c->string));cisNULLwhen the program crashes as you try to accessc->string.