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❮ C Function Atof C Examples Printf Char ❯

C Standard Library - <stddef.h>

Introduction

The stddef.h header file defines various variable types and macros. Many of these definitions are also found in other header files.

Library Variables

Below are the variable types defined in the stddef.h header file:

No. Variable & Description
1 ptrdiff_t <br>This is a signed integer type, which is the result of subtracting two pointers.
2 size_t <br>This is an unsigned integer type, which is the result of the sizeof keyword.
3 wchar_t <br>This is an integer type of wide character constants.

Library Macros

Below are the macros defined in the stddef.h header file:

No. Macro & Description
1 NULL <br>This macro is the value of a null pointer constant.
2 offsetof(type, member-designator) <br>This generates a constant integer of type size_t, which is the byte offset of a structure member relative to the beginning of the structure. The member is given by member-designator, and the structure's name is given in type.
❮ C Function Atof C Examples Printf Char ❯