man3type/intptr_t.3type

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   7 .TH INTPTR_T 3type 2022-02-25 "Linux man-pages (unreleased)"
   8 .SH NAME
   9 intptr_t, uintptr_t \- integer types wide enough to hold pointers
  10 .SH LIBRARY
  11 Standard C library
  12 .RI ( libc )
  13 .SH SYNOPSIS
  14 .nf
  15 .B #include <stdint.h>
  16 .PP
  17 .BR typedef " /* ... */ " intptr_t;
  18 .BR typedef " /* ... */ " uintptr_t;
  19 .PP
  20 .BR "#define INTPTR_WIDTH" "  /* ... */"
  21 .B #define UINTPTR_WIDTH INTPTR_WIDTH
  22 .PP
  23 .BR "#define INTPTR_MAX" "    /*  2**(INTPTR_WIDTH \- 1) \- 1  */"
  24 .BR "#define INTPTR_MIN" "    /*  \- 2**(INTPTR_WIDTH \- 1)    */"
  25 .BR "#define UINTPTR_MAX" "   /*  2**UINTPTR_WIDTH \- 1       */"
  26 .fi
  27 .SH DESCRIPTION
  28 .I intptr_t
  29 is a signed integer type
  30 such that any valid
  31 .RI ( "void *" )
  32 value can be converted to this type and then converted back.
  33 It is capable of storing values in the range
  34 .RB [ INTPTR_MIN ,
  35 .BR INTPTR_MAX ].
  36 .PP
  37 .I uintptr_t
  38 is an unsigned integer type
  39 such that any valid
  40 .RI ( "void *" )
  41 value can be converted to this type and then converted back.
  42 It is capable of storing values in the range
  43 .RB [ 0 ,
  44 .BR INTPTR_MAX ].
  45 .PP
  46 The macros
  47 .RB [ U ] INTPTR_WIDTH
  48 expand to the width in bits of these types.
  49 .PP
  50 The macros
  51 .RB [ U ] INTPTR_MAX
  52 expand to the maximum value that these types can hold.
  53 .PP
  54 The macro
  55 .B INTPTR_MIN
  56 expands to the minimum value that
  57 .I intptr_t
  58 can hold.
  59 .PP
  60 The length modifiers for the
  61 .RI [ u ] intptr_t
  62 types
  63 for the
  64 .BR printf (3)
  65 family of functions
  66 are expanded by the macros
  67 .BR PRIdPTR ,
  68 .BR PRIiPTR ,
  69 and
  70 .B PRIuPTR
  71 (defined in
  72 .IR <inttypes.h> );
  73 resulting commonly in
  74 .B %"PRIdPTR"
  75 or
  76 .B %"PRIiPTR"
  77 for printing
  78 .I intptr_t
  79 values.
  80 The length modifiers for the
  81 .IR [ u ] intptr_t
  82 types
  83 for the
  84 .BR scanf (3)
  85 family of functions
  86 are expanded by the macros
  87 .BR SCNdPTR ,
  88 .BR SCNiPTR ,
  89 and
  90 .B SCNuPTR
  91 (defined in
  92 .IR <inttypes.h> );
  93 resulting commonly in
  94 .B %"SCNuPTR"
  95 for scanning
  96 .I uintptr_t
  97 values.
  98 .SH STANDARDS
  99 C99 and later; POSIX.1-2001 and later.
 100 .SH NOTES
 101 The following header also provides these types:
 102 .IR <inttypes.h> .
 103 .SH SEE ALSO
 104 .BR intmax_t (3type),
 105 .BR void (3)