In C copy data defined in code into a memory location of a char pointer?

Question

So let's say I have code similar to something like this.

#define DATA 0x67
char *mydata = malloc(1);
mydata = DATA

Line 3 is invalid, of course, but what I am looking of is to take 0x67 and read it into that memory location. It must be obvious, but I don't know what that would be called to ask the question properly.

Answer 1

Dereference the pointer is equivalent to access the first indice of an array (in this case an array of char) which is maybe more easily understandable:

#define DATA 0x67
char *mydata = malloc(1);
mydata[0] = DATA

If you would have allocated more memory you could access all bytes of this memory this way.

Answer 2

you need to 'derefernce' the pointer

#define DATA 0x67
char *mydata = malloc(1);
*mydata = DATA

think of it this way.

char *mydata

says that *mydata is a char, you can assign DATA to a char