#include <stdint.h> typedef /* ... */ intptr_t; typedef /* ... */ uintptr_t; #define INTPTR_WIDTH /* ... */ #define UINTPTR_WIDTH INTPTR_WIDTH #define INTPTR_MAX /* 2**(INTPTR_WIDTH - 1) - 1 */ #define INTPTR_MIN /* - 2**(INTPTR_WIDTH - 1) */ #define UINTPTR_MAX /* 2**UINTPTR_WIDTH - 1 */
uintptr_t is an unsigned integer type such that any valid (void *) value can be converted to this type and then converted back. It is capable of storing values in the range [0, INTPTR_MAX].
The macros [U]INTPTR_WIDTH expand to the width in bits of these types.
The macros [U]INTPTR_MAX expand to the maximum value that these types can hold.
The macro INTPTR_MIN expands to the minimum value that intptr_t can hold.
The length modifiers for the [u]intptr_t types for the printf(3) family of functions are expanded by the macros PRIdPTR, PRIiPTR, and PRIuPTR (defined in <inttypes.h>); resulting commonly in %PRIdPTR or %PRIiPTR for printing intptr_t values. The length modifiers for the [u]intptr_t types for the scanf(3) family of functions are expanded by the macros SCNdPTR, SCNiPTR, and SCNuPTR (defined in <inttypes.h>); resulting commonly in %SCNuPTR for scanning uintptr_t values.