Defined in header <math.h>

Defined in header <string.h>

Defined in header <complex.h>

Defined in header <wchar.h>

Defined in header <math.h>

Includes another source file into the current source file at the line immediately after the directive. Syntax

When an identifier is encountered in a C program, a lookup is performed

Defined in header <stdlib.h>

Defined in header <math.h>

Defined in header <threads.h>