[444] | 1 | /* |
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| 2 | * Copyright (c) 1990 The Regents of the University of California. |
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| 3 | * All rights reserved. |
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| 4 | * |
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| 5 | * Redistribution and use in source and binary forms are permitted |
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| 6 | * provided that the above copyright notice and this paragraph are |
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| 7 | * duplicated in all such forms and that any documentation, |
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| 8 | * advertising materials, and other materials related to such |
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| 9 | * distribution and use acknowledge that the software was developed |
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| 10 | * by the University of California, Berkeley. The name of the |
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| 11 | * University may not be used to endorse or promote products derived |
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| 12 | * from this software without specific prior written permission. |
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| 13 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
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| 14 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
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| 15 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
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| 16 | */ |
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| 17 | |
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| 18 | /* |
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| 19 | FUNCTION |
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| 20 | <<sprintf>>, <<fprintf>>, <<printf>>, <<snprintf>>, <<asprintf>>, <<asnprintf>>---format output |
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| 21 | |
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| 22 | INDEX |
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| 23 | fprintf |
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| 24 | INDEX |
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| 25 | _fprintf_r |
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| 26 | INDEX |
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| 27 | printf |
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| 28 | INDEX |
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| 29 | _printf_r |
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| 30 | INDEX |
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| 31 | asprintf |
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| 32 | INDEX |
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| 33 | _asprintf_r |
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| 34 | INDEX |
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| 35 | sprintf |
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| 36 | INDEX |
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| 37 | _sprintf_r |
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| 38 | INDEX |
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| 39 | snprintf |
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| 40 | INDEX |
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| 41 | _snprintf_r |
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| 42 | INDEX |
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| 43 | asnprintf |
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| 44 | INDEX |
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| 45 | _asnprintf_r |
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| 46 | |
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| 47 | SYNOPSIS |
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| 48 | #include <stdio.h> |
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| 49 | |
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| 50 | int printf(const char *restrict <[format]>, ...); |
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| 51 | int fprintf(FILE *restrict <[fd]>, const char *restrict <[format]>, ...); |
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| 52 | int sprintf(char *restrict <[str]>, const char *restrict <[format]>, ...); |
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| 53 | int snprintf(char *restrict <[str]>, size_t <[size]>, const char *restrict <[format]>, |
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| 54 | ...); |
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| 55 | int asprintf(char **restrict <[strp]>, const char *restrict <[format]>, ...); |
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| 56 | char *asnprintf(char *restrict <[str]>, size_t *restrict <[size]>, const char *restrict <[format]>, |
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| 57 | ...); |
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| 58 | |
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| 59 | int _printf_r(struct _reent *<[ptr]>, const char *restrict <[format]>, ...); |
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| 60 | int _fprintf_r(struct _reent *<[ptr]>, FILE *restrict <[fd]>, |
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| 61 | const char *restrict <[format]>, ...); |
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| 62 | int _sprintf_r(struct _reent *<[ptr]>, char *restrict <[str]>, |
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| 63 | const char *restrict <[format]>, ...); |
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| 64 | int _snprintf_r(struct _reent *<[ptr]>, char *restrict <[str]>, size_t <[size]>, |
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| 65 | const char *restrict <[format]>, ...); |
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| 66 | int _asprintf_r(struct _reent *<[ptr]>, char **restrict <[strp]>, |
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| 67 | const char *restrict <[format]>, ...); |
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| 68 | char *_asnprintf_r(struct _reent *<[ptr]>, char *restrict <[str]>, |
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| 69 | size_t *restrict <[size]>, const char *restrict <[format]>, ...); |
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| 70 | |
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| 71 | DESCRIPTION |
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| 72 | <<printf>> accepts a series of arguments, applies to each a |
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| 73 | format specifier from <<*<[format]>>>, and writes the |
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| 74 | formatted data to <<stdout>>, without a terminating NUL |
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| 75 | character. The behavior of <<printf>> is undefined if there |
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| 76 | are not enough arguments for the format. <<printf>> returns |
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| 77 | when it reaches the end of the format string. If there are |
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| 78 | more arguments than the format requires, excess arguments are |
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| 79 | ignored. |
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| 80 | |
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| 81 | <<fprintf>> is like <<printf>>, except that output is directed |
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| 82 | to the stream <[fd]> rather than <<stdout>>. |
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| 83 | |
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| 84 | <<sprintf>> is like <<printf>>, except that output is directed |
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| 85 | to the buffer <[str]>, and a terminating NUL is output. |
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| 86 | Behavior is undefined if more output is generated than the |
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| 87 | buffer can hold. |
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| 88 | |
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| 89 | <<snprintf>> is like <<sprintf>>, except that output is |
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| 90 | limited to at most <[size]> bytes, including the terminating |
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| 91 | <<NUL>>. As a special case, if <[size]> is 0, <[str]> can be |
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| 92 | NULL, and <<snprintf>> merely calculates how many bytes would |
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| 93 | be printed. |
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| 94 | |
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| 95 | <<asprintf>> is like <<sprintf>>, except that the output is |
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| 96 | stored in a dynamically allocated buffer, <[pstr]>, which |
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| 97 | should be freed later with <<free>>. |
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| 98 | |
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| 99 | <<asnprintf>> is like <<sprintf>>, except that the return type |
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| 100 | is either the original <[str]> if it was large enough, or a |
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| 101 | dynamically allocated string if the output exceeds *<[size]>; |
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| 102 | the length of the result is returned in *<[size]>. When |
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| 103 | dynamic allocation occurs, the contents of the original |
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| 104 | <[str]> may have been modified. |
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| 105 | |
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| 106 | For <<sprintf>>, <<snprintf>>, and <<asnprintf>>, the behavior |
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| 107 | is undefined if the output <<*<[str]>>> overlaps with one of |
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| 108 | the arguments. Behavior is also undefined if the argument for |
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| 109 | <<%n>> within <<*<[format]>>> overlaps another argument. |
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| 110 | |
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| 111 | <[format]> is a pointer to a character string containing two |
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| 112 | types of objects: ordinary characters (other than <<%>>), |
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| 113 | which are copied unchanged to the output, and conversion |
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| 114 | specifications, each of which is introduced by <<%>>. (To |
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| 115 | include <<%>> in the output, use <<%%>> in the format string.) |
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| 116 | A conversion specification has the following form: |
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| 117 | |
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| 118 | . %[<[pos]>][<[flags]>][<[width]>][.<[prec]>][<[size]>]<[type]> |
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| 119 | |
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| 120 | The fields of the conversion specification have the following |
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| 121 | meanings: |
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| 122 | |
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| 123 | O+ |
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| 124 | o <[pos]> |
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| 125 | |
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| 126 | Conversions normally consume arguments in the order that they |
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| 127 | are presented. However, it is possible to consume arguments |
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| 128 | out of order, and reuse an argument for more than one |
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| 129 | conversion specification (although the behavior is undefined |
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| 130 | if the same argument is requested with different types), by |
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| 131 | specifying <[pos]>, which is a decimal integer followed by |
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| 132 | '$'. The integer must be between 1 and <NL_ARGMAX> from |
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| 133 | limits.h, and if argument <<%n$>> is requested, all earlier |
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| 134 | arguments must be requested somewhere within <[format]>. If |
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| 135 | positional parameters are used, then all conversion |
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| 136 | specifications except for <<%%>> must specify a position. |
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| 137 | This positional parameters method is a POSIX extension to the C |
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| 138 | standard definition for the functions. |
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| 139 | |
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| 140 | o <[flags]> |
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| 141 | |
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| 142 | <[flags]> is an optional sequence of characters which control |
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| 143 | output justification, numeric signs, decimal points, trailing |
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| 144 | zeros, and octal and hex prefixes. The flag characters are |
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| 145 | minus (<<->>), plus (<<+>>), space ( ), zero (<<0>>), sharp |
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| 146 | (<<#>>), and quote (<<'>>). They can appear in any |
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| 147 | combination, although not all flags can be used for all |
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| 148 | conversion specification types. |
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| 149 | |
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| 150 | o+ |
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| 151 | o ' |
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| 152 | A POSIX extension to the C standard. However, this |
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| 153 | implementation presently treats it as a no-op, which |
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| 154 | is the default behavior for the C locale, anyway. (If |
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| 155 | it did what it is supposed to, when <[type]> were <<i>>, |
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| 156 | <<d>>, <<u>>, <<f>>, <<F>>, <<g>>, or <<G>>, the |
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| 157 | integer portion of the conversion would be formatted |
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| 158 | with thousands' grouping wide characters.) |
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| 159 | |
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| 160 | o - |
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| 161 | The result of the conversion is left |
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| 162 | justified, and the right is padded with |
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| 163 | blanks. If you do not use this flag, the |
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| 164 | result is right justified, and padded on the |
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| 165 | left. |
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| 166 | |
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| 167 | o + |
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| 168 | The result of a signed conversion (as |
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| 169 | determined by <[type]> of <<d>>, <<i>>, <<a>>, |
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| 170 | <<A>>, <<e>>, <<E>>, <<f>>, <<F>>, <<g>>, or |
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| 171 | <<G>>) will always begin with a plus or minus |
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| 172 | sign. (If you do not use this flag, positive |
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| 173 | values do not begin with a plus sign.) |
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| 174 | |
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| 175 | o " " (space) |
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| 176 | If the first character of a signed conversion |
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| 177 | specification is not a sign, or if a signed |
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| 178 | conversion results in no characters, the |
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| 179 | result will begin with a space. If the space |
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| 180 | ( ) flag and the plus (<<+>>) flag both |
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| 181 | appear, the space flag is ignored. |
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| 182 | |
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| 183 | o 0 |
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| 184 | If the <[type]> character is <<d>>, <<i>>, |
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| 185 | <<o>>, <<u>>, <<x>>, <<X>>, <<a>>, <<A>>, |
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| 186 | <<e>>, <<E>>, <<f>>, <<F>>, <<g>>, or <<G>>: leading |
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| 187 | zeros are used to pad the field width |
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| 188 | (following any indication of sign or base); no |
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| 189 | spaces are used for padding. If the zero |
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| 190 | (<<0>>) and minus (<<->>) flags both appear, |
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| 191 | the zero (<<0>>) flag will be ignored. For |
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| 192 | <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, and <<X>> |
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| 193 | conversions, if a precision <[prec]> is |
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| 194 | specified, the zero (<<0>>) flag is ignored. |
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| 195 | |
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| 196 | Note that <<0>> is interpreted as a flag, not |
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| 197 | as the beginning of a field width. |
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| 198 | |
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| 199 | o # |
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| 200 | The result is to be converted to an |
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| 201 | alternative form, according to the <[type]> |
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| 202 | character. |
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| 203 | o- |
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| 204 | |
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| 205 | The alternative form output with the # flag depends on the <[type]> |
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| 206 | character: |
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| 207 | |
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| 208 | o+ |
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| 209 | o o |
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| 210 | Increases precision to force the first |
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| 211 | digit of the result to be a zero. |
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| 212 | |
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| 213 | o x |
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| 214 | A non-zero result will have a <<0x>> |
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| 215 | prefix. |
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| 216 | |
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| 217 | o X |
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| 218 | A non-zero result will have a <<0X>> |
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| 219 | prefix. |
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| 220 | |
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| 221 | o a, A, e, E, f, or F |
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| 222 | The result will always contain a |
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| 223 | decimal point even if no digits follow |
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| 224 | the point. (Normally, a decimal point |
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| 225 | appears only if a digit follows it.) |
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| 226 | Trailing zeros are removed. |
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| 227 | |
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| 228 | o g or G |
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| 229 | The result will always contain a |
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| 230 | decimal point even if no digits follow |
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| 231 | the point. Trailing zeros are not |
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| 232 | removed. |
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| 233 | |
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| 234 | o all others |
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| 235 | Undefined. |
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| 236 | |
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| 237 | o- |
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| 238 | |
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| 239 | o <[width]> |
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| 240 | |
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| 241 | <[width]> is an optional minimum field width. You can |
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| 242 | either specify it directly as a decimal integer, or |
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| 243 | indirectly by using instead an asterisk (<<*>>), in |
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| 244 | which case an <<int>> argument is used as the field |
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| 245 | width. If positional arguments are used, then the |
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| 246 | width must also be specified positionally as <<*m$>>, |
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| 247 | with m as a decimal integer. Negative field widths |
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| 248 | are treated as specifying the minus (<<->>) flag for |
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| 249 | left justfication, along with a positive field width. |
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| 250 | The resulting format may be wider than the specified |
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| 251 | width. |
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| 252 | |
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| 253 | o <[prec]> |
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| 254 | |
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| 255 | <[prec]> is an optional field; if present, it is |
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| 256 | introduced with `<<.>>' (a period). You can specify |
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| 257 | the precision either directly as a decimal integer or |
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| 258 | indirectly by using an asterisk (<<*>>), in which case |
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| 259 | an <<int>> argument is used as the precision. If |
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| 260 | positional arguments are used, then the precision must |
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| 261 | also be specified positionally as <<*m$>>, with m as a |
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| 262 | decimal integer. Supplying a negative precision is |
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| 263 | equivalent to omitting the precision. If only a |
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| 264 | period is specified the precision is zero. The effect |
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| 265 | depends on the conversion <[type]>. |
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| 266 | |
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| 267 | o+ |
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| 268 | o d, i, o, u, x, or X |
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| 269 | Minimum number of digits to appear. If no |
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| 270 | precision is given, defaults to 1. |
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| 271 | |
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| 272 | o a or A |
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| 273 | Number of digits to appear after the decimal |
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| 274 | point. If no precision is given, the |
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| 275 | precision defaults to the minimum needed for |
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| 276 | an exact representation. |
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| 277 | |
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| 278 | o e, E, f or F |
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| 279 | Number of digits to appear after the decimal |
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| 280 | point. If no precision is given, the |
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| 281 | precision defaults to 6. |
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| 282 | |
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| 283 | o g or G |
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| 284 | Maximum number of significant digits. A |
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| 285 | precision of 0 is treated the same as a |
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| 286 | precision of 1. If no precision is given, the |
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| 287 | precision defaults to 6. |
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| 288 | |
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| 289 | o s or S |
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| 290 | Maximum number of characters to print from the |
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| 291 | string. If no precision is given, the entire |
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| 292 | string is printed. |
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| 293 | |
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| 294 | o all others |
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| 295 | undefined. |
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| 296 | |
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| 297 | o- |
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| 298 | |
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| 299 | o <[size]> |
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| 300 | |
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| 301 | <[size]> is an optional modifier that changes the data |
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| 302 | type that the corresponding argument has. Behavior is |
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| 303 | unspecified if a size is given that does not match the |
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| 304 | <[type]>. |
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| 305 | |
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| 306 | o+ |
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| 307 | o hh |
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| 308 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 309 | <<X>>, specifies that the argument should be |
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| 310 | converted to a <<signed char>> or <<unsigned |
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| 311 | char>> before printing. |
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| 312 | |
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| 313 | With <<n>>, specifies that the argument is a |
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| 314 | pointer to a <<signed char>>. |
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| 315 | |
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| 316 | o h |
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| 317 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 318 | <<X>>, specifies that the argument should be |
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| 319 | converted to a <<short>> or <<unsigned short>> |
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| 320 | before printing. |
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| 321 | |
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| 322 | With <<n>>, specifies that the argument is a |
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| 323 | pointer to a <<short>>. |
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| 324 | |
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| 325 | o l |
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| 326 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 327 | <<X>>, specifies that the argument is a |
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| 328 | <<long>> or <<unsigned long>>. |
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| 329 | |
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| 330 | With <<c>>, specifies that the argument has |
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| 331 | type <<wint_t>>. |
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| 332 | |
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| 333 | With <<s>>, specifies that the argument is a |
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| 334 | pointer to <<wchar_t>>. |
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| 335 | |
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| 336 | With <<n>>, specifies that the argument is a |
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| 337 | pointer to a <<long>>. |
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| 338 | |
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| 339 | With <<a>>, <<A>>, <<e>>, <<E>>, <<f>>, <<F>>, |
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| 340 | <<g>>, or <<G>>, has no effect (because of |
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| 341 | vararg promotion rules, there is no need to |
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| 342 | distinguish between <<float>> and <<double>>). |
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| 343 | |
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| 344 | o ll |
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| 345 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 346 | <<X>>, specifies that the argument is a |
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| 347 | <<long long>> or <<unsigned long long>>. |
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| 348 | |
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| 349 | With <<n>>, specifies that the argument is a |
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| 350 | pointer to a <<long long>>. |
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| 351 | |
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| 352 | o j |
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| 353 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 354 | <<X>>, specifies that the argument is an |
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| 355 | <<intmax_t>> or <<uintmax_t>>. |
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| 356 | |
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| 357 | With <<n>>, specifies that the argument is a |
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| 358 | pointer to an <<intmax_t>>. |
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| 359 | |
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| 360 | o z |
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| 361 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 362 | <<X>>, specifies that the argument is a <<size_t>>. |
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| 363 | |
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| 364 | With <<n>>, specifies that the argument is a |
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| 365 | pointer to a <<size_t>>. |
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| 366 | |
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| 367 | o t |
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| 368 | With <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, or |
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| 369 | <<X>>, specifies that the argument is a |
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| 370 | <<ptrdiff_t>>. |
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| 371 | |
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| 372 | With <<n>>, specifies that the argument is a |
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| 373 | pointer to a <<ptrdiff_t>>. |
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| 374 | |
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| 375 | o L |
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| 376 | With <<a>>, <<A>>, <<e>>, <<E>>, <<f>>, <<F>>, |
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| 377 | <<g>>, or <<G>>, specifies that the argument |
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| 378 | is a <<long double>>. |
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| 379 | |
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| 380 | o- |
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| 381 | |
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| 382 | o <[type]> |
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| 383 | |
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| 384 | <[type]> specifies what kind of conversion <<printf>> |
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| 385 | performs. Here is a table of these: |
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| 386 | |
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| 387 | o+ |
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| 388 | o % |
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| 389 | Prints the percent character (<<%>>). |
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| 390 | |
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| 391 | o c |
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| 392 | Prints <[arg]> as single character. If the |
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| 393 | <<l>> size specifier is in effect, a multibyte |
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| 394 | character is printed. |
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| 395 | |
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| 396 | o C |
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| 397 | Short for <<%lc>>. A POSIX extension to the C standard. |
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| 398 | |
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| 399 | o s |
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| 400 | Prints the elements of a pointer to <<char>> |
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| 401 | until the precision or a null character is |
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| 402 | reached. If the <<l>> size specifier is in |
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| 403 | effect, the pointer is to an array of |
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| 404 | <<wchar_t>>, and the string is converted to |
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| 405 | multibyte characters before printing. |
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| 406 | |
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| 407 | o S |
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| 408 | Short for <<%ls>>. A POSIX extension to the C standard. |
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| 409 | |
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| 410 | o d or i |
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| 411 | Prints a signed decimal integer; takes an |
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| 412 | <<int>>. Leading zeros are inserted as |
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| 413 | necessary to reach the precision. A value of 0 with |
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| 414 | a precision of 0 produces an empty string. |
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| 415 | |
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| 416 | o D |
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| 417 | Newlib extension, short for <<%ld>>. |
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| 418 | |
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| 419 | o o |
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| 420 | Prints an unsigned octal integer; takes an |
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| 421 | <<unsigned>>. Leading zeros are inserted as |
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| 422 | necessary to reach the precision. A value of 0 with |
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| 423 | a precision of 0 produces an empty string. |
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| 424 | |
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| 425 | o O |
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| 426 | Newlib extension, short for <<%lo>>. |
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| 427 | |
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| 428 | o u |
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| 429 | Prints an unsigned decimal integer; takes an |
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| 430 | <<unsigned>>. Leading zeros are inserted as |
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| 431 | necessary to reach the precision. A value of 0 with |
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| 432 | a precision of 0 produces an empty string. |
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| 433 | |
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| 434 | o U |
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| 435 | Newlib extension, short for <<%lu>>. |
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| 436 | |
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| 437 | o x |
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| 438 | Prints an unsigned hexadecimal integer (using |
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| 439 | <<abcdef>> as digits beyond <<9>>); takes an |
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| 440 | <<unsigned>>. Leading zeros are inserted as |
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| 441 | necessary to reach the precision. A value of 0 with |
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| 442 | a precision of 0 produces an empty string. |
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| 443 | |
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| 444 | o X |
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| 445 | Like <<x>>, but uses <<ABCDEF>> as digits |
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| 446 | beyond <<9>>. |
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| 447 | |
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| 448 | o f |
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| 449 | Prints a signed value of the form |
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| 450 | <<[-]9999.9999>>, with the precision |
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| 451 | determining how many digits follow the decimal |
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| 452 | point; takes a <<double>> (remember that |
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| 453 | <<float>> promotes to <<double>> as a vararg). |
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| 454 | The low order digit is rounded to even. If |
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| 455 | the precision results in at most DECIMAL_DIG |
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| 456 | digits, the result is rounded correctly; if |
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| 457 | more than DECIMAL_DIG digits are printed, the |
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| 458 | result is only guaranteed to round back to the |
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| 459 | original value. |
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| 460 | |
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| 461 | If the value is infinite, the result is |
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| 462 | <<inf>>, and no zero padding is performed. If |
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| 463 | the value is not a number, the result is |
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| 464 | <<nan>>, and no zero padding is performed. |
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| 465 | |
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| 466 | o F |
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| 467 | Like <<f>>, but uses <<INF>> and <<NAN>> for |
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| 468 | non-finite numbers. |
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| 469 | |
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| 470 | o e |
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| 471 | Prints a signed value of the form |
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| 472 | <<[-]9.9999e[+|-]999>>; takes a <<double>>. |
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| 473 | The digit before the decimal point is non-zero |
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| 474 | if the value is non-zero. The precision |
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| 475 | determines how many digits appear between |
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| 476 | <<.>> and <<e>>, and the exponent always |
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| 477 | contains at least two digits. The value zero |
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| 478 | has an exponent of zero. If the value is not |
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| 479 | finite, it is printed like <<f>>. |
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| 480 | |
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| 481 | o E |
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| 482 | Like <<e>>, but using <<E>> to introduce the |
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| 483 | exponent, and like <<F>> for non-finite |
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| 484 | values. |
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| 485 | |
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| 486 | o g |
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| 487 | Prints a signed value in either <<f>> or <<e>> |
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| 488 | form, based on the given value and |
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| 489 | precision---an exponent less than -4 or |
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| 490 | greater than the precision selects the <<e>> |
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| 491 | form. Trailing zeros and the decimal point |
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| 492 | are printed only if necessary; takes a |
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| 493 | <<double>>. |
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| 494 | |
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| 495 | o G |
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| 496 | Like <<g>>, except use <<F>> or <<E>> form. |
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| 497 | |
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| 498 | o a |
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| 499 | Prints a signed value of the form |
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| 500 | <<[-]0x1.ffffp[+|-]9>>; takes a <<double>>. |
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| 501 | The letters <<abcdef>> are used for digits |
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| 502 | beyond <<9>>. The precision determines how |
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| 503 | many digits appear after the decimal point. |
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| 504 | The exponent contains at least one digit, and |
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| 505 | is a decimal value representing the power of |
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| 506 | 2; a value of 0 has an exponent of 0. |
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| 507 | Non-finite values are printed like <<f>>. |
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| 508 | |
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| 509 | o A |
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| 510 | Like <<a>>, except uses <<X>>, <<P>>, and |
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| 511 | <<ABCDEF>> instead of lower case. |
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| 512 | |
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| 513 | o n |
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| 514 | Takes a pointer to <<int>>, and stores a count |
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| 515 | of the number of bytes written so far. No |
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| 516 | output is created. |
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| 517 | |
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| 518 | o p |
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| 519 | Takes a pointer to <<void>>, and prints it in |
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| 520 | an implementation-defined format. This |
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| 521 | implementation is similar to <<%#tx>>), except |
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| 522 | that <<0x>> appears even for the NULL pointer. |
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| 523 | |
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| 524 | o m |
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| 525 | Prints the output of <<strerror(errno)>>; no |
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| 526 | argument is required. A GNU extension. |
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| 527 | |
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| 528 | o- |
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| 529 | O- |
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| 530 | |
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| 531 | <<_printf_r>>, <<_fprintf_r>>, <<_asprintf_r>>, |
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| 532 | <<_sprintf_r>>, <<_snprintf_r>>, <<_asnprintf_r>> are simply |
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| 533 | reentrant versions of the functions above. |
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| 534 | |
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| 535 | RETURNS |
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| 536 | On success, <<sprintf>> and <<asprintf>> return the number of bytes in |
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| 537 | the output string, except the concluding <<NUL>> is not counted. |
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| 538 | <<snprintf>> returns the number of bytes that would be in the output |
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| 539 | string, except the concluding <<NUL>> is not counted. <<printf>> and |
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| 540 | <<fprintf>> return the number of characters transmitted. |
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| 541 | <<asnprintf>> returns the original <[str]> if there was enough room, |
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| 542 | otherwise it returns an allocated string. |
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| 543 | |
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| 544 | If an error occurs, the result of <<printf>>, <<fprintf>>, |
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| 545 | <<snprintf>>, and <<asprintf>> is a negative value, and the result of |
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| 546 | <<asnprintf>> is NULL. No error returns occur for <<sprintf>>. For |
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| 547 | <<printf>> and <<fprintf>>, <<errno>> may be set according to |
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| 548 | <<fputc>>. For <<asprintf>> and <<asnprintf>>, <<errno>> may be set |
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| 549 | to ENOMEM if allocation fails, and for <<snprintf>>, <<errno>> may be |
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| 550 | set to EOVERFLOW if <[size]> or the output length exceeds INT_MAX. |
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| 551 | |
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| 552 | BUGS |
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| 553 | The ``''' (quote) flag does not work when locale's thousands_sep is not empty. |
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| 554 | |
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| 555 | PORTABILITY |
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| 556 | ANSI C requires <<printf>>, <<fprintf>>, <<sprintf>>, and |
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| 557 | <<snprintf>>. <<asprintf>> and <<asnprintf>> are newlib extensions. |
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| 558 | |
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| 559 | The ANSI C standard specifies that implementations must support at |
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| 560 | least formatted output of up to 509 characters. This implementation |
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| 561 | has no inherent limit. |
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| 562 | |
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| 563 | Depending on how newlib was configured, not all format specifiers are |
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| 564 | supported. |
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| 565 | |
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| 566 | Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>, |
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| 567 | <<lseek>>, <<read>>, <<sbrk>>, <<write>>. |
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| 568 | */ |
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| 569 | |
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| 570 | #include <_ansi.h> |
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| 571 | #include <reent.h> |
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| 572 | #include <stdio.h> |
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| 573 | #include <stdarg.h> |
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| 574 | #include <limits.h> |
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| 575 | #include "local.h" |
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| 576 | |
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| 577 | int |
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| 578 | _sprintf_r (struct _reent *ptr, |
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| 579 | char *__restrict str, |
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| 580 | const char *__restrict fmt, ...) |
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| 581 | { |
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| 582 | int ret; |
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| 583 | va_list ap; |
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| 584 | FILE f; |
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| 585 | |
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| 586 | f._flags = __SWR | __SSTR; |
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| 587 | f._bf._base = f._p = (unsigned char *) str; |
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| 588 | f._bf._size = f._w = INT_MAX; |
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| 589 | f._file = -1; /* No file. */ |
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| 590 | va_start (ap, fmt); |
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| 591 | ret = _svfprintf_r (ptr, &f, fmt, ap); |
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| 592 | va_end (ap); |
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| 593 | *f._p = '\0'; /* terminate the string */ |
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| 594 | return (ret); |
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| 595 | } |
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| 596 | |
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| 597 | #ifdef _NANO_FORMATTED_IO |
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| 598 | int |
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| 599 | _siprintf_r (struct _reent *, char *, const char *, ...) |
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| 600 | _ATTRIBUTE ((__alias__("_sprintf_r"))); |
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| 601 | #endif |
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| 602 | |
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| 603 | #ifndef _REENT_ONLY |
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| 604 | |
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| 605 | int |
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| 606 | sprintf (char *__restrict str, |
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| 607 | const char *__restrict fmt, ...) |
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| 608 | { |
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| 609 | int ret; |
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| 610 | va_list ap; |
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| 611 | FILE f; |
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| 612 | |
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| 613 | f._flags = __SWR | __SSTR; |
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| 614 | f._bf._base = f._p = (unsigned char *) str; |
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| 615 | f._bf._size = f._w = INT_MAX; |
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| 616 | f._file = -1; /* No file. */ |
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| 617 | va_start (ap, fmt); |
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| 618 | ret = _svfprintf_r (_REENT, &f, fmt, ap); |
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| 619 | va_end (ap); |
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| 620 | *f._p = '\0'; /* terminate the string */ |
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| 621 | return (ret); |
---|
| 622 | } |
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| 623 | |
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| 624 | #ifdef _NANO_FORMATTED_IO |
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| 625 | int |
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| 626 | siprintf (char *, const char *, ...) |
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| 627 | _ATTRIBUTE ((__alias__("sprintf"))); |
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| 628 | #endif |
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| 629 | #endif |
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