Meaning of (indirect member operator) in C language

Written on December 12, 2016.

"," is called an indirect member operator.

General Note: This operator is used with pointers to structs (STURCT) or unions (union) to indicate the members of a struct or union. Suppose Ptrstr is a pointer to a struct, member is a member specified by the structure template.

So

Ptrstr->member

This expression represents the member of the structure being pointed to. Indirect member operators can also be used in the same way for unions.

Example

struct{

int code;

float cost;

} Item *ptrstr;

ptrstr=&item;

ptrstr->code=3451;

The last statement first points ptrstr to code, and then assigns an int value of 3451 to the member of item code. The following three expressions are equivalent:

Ptrstr->code

Item.code

(*PTRSTR). Code

Meaning of (indirect member operator) in C language