c++ - C/ObjC - parameter size. Using a pointer vs value -

at point should passing pointer data in functions/methods, rather passing value?

obviously there's cases want function operate on given data, if i'm passing value info/copying purposes?

for example, foo basic type:

void setfoo(int foo); ... int foo = 1; setfoo(foo); 

now foo simple structure:

typedef struct {     int x;     int y; } foo;  void setfoo(foo foo); ... foo foo = {1, 2}; setfoo(foo);   // apple code kind of thing cgsize, cgpoint... 

but if foo bigger struct...

typedef struct {     int x;     int y;     int z;     char str[256]; } foo;  void setfoo(foo *foo);  // taking pointer instead. ... foo foo = {1, 2, 3, etc ... }; setfoo(&foo); 

q. @ point here should start using pointer when providing data function?

thanks

when on embedded systems, think it's practice pass pointers (or references) that's not primitive type. way struct can grow , add members needed without affecting amount of data copied. needless copying way slow down system, avoid when can. getting habit in long run think.