Holtek HT-IDE, User Manual

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Structures and Unions
→
Structures
•
Syntax
struct
struct-name
{
data-type member1;
data-type member2;
...
data-type membern;
} [
variable-list];
•
Description
A structure is a collection of one or more variables, possibly of different
types, grouped together under a single name for convenient handling.
Structures may be copied and assigned to, passed to functions and
returned by functions. C allows bit fields. Nested structures are also
allowed.
The reserved word struct indicates a structure is to be defined while
struct-name is the name of the structure. Within the structure, data-
type is one of the valid data types. Members within the structure may
have different data types. The variable-list declares variables of the
type struct-name. Each item in the structure is refered to as a member.
After defining a structure, other variables of the same type are declared
with the following syntax:
struct
struct-name variable-list;
To access a member of a structure, specify the name of the variable and
the name of member separated by a period. The syntax is
svariable
.
member1
where svariable is the variable of structure type and member1 is a
member of the structure. A structure member can have a data type with
a previously defined structure. This is referred to as a nested structure.
•
Example
struct person_id
{
char id_num[6];
char name[3];
unsigned long birth_date;
} mark;
Chapter 9 Holtek C Language
101