intptr_t(3type)

NAME
intptr_t, uintptr_t - integer types wide enough to hold pointers

LIBRARY
Standard C library (libc)

SYNOPSIS
#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       */

DESCRIPTION
intptr_t is a signed 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 [INTPTR_MIN, INTPTR_MAX].

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, UINTPTR_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.

STANDARDS

[u]intptr_t
[U]INTPTR_MAX
INTPTR_MIN
    C23, POSIX.1-2024.

[U]INTPTR_WIDTH
    C23.

HISTORY

[u]intptr_t
    SUSv2, C99, POSIX.1-2001 XSI.

[U]INTPTR_MAX
INTPTR_MIN
    C99, POSIX.1-2001 XSI.

[U]INTPTR_WIDTH
    C23.

NOTES
The following header also provides these types: <inttypes.h>.

SEE ALSO
intmax_t(3type), void(3)