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> |
---|
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; |
---|
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); |
---|
592 | va_end (ap); |
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593 | *f._p = '\0'; /* terminate the string */ |
---|
594 | return (ret); |
---|
595 | } |
---|
596 | |
---|
597 | #ifdef _NANO_FORMATTED_IO |
---|
598 | int |
---|
599 | _siprintf_r (struct _reent *, char *, const char *, ...) |
---|
600 | _ATTRIBUTE ((__alias__("_sprintf_r"))); |
---|
601 | #endif |
---|
602 | |
---|
603 | #ifndef _REENT_ONLY |
---|
604 | |
---|
605 | int |
---|
606 | sprintf (char *__restrict str, |
---|
607 | const char *__restrict fmt, ...) |
---|
608 | { |
---|
609 | int ret; |
---|
610 | va_list ap; |
---|
611 | FILE f; |
---|
612 | |
---|
613 | f._flags = __SWR | __SSTR; |
---|
614 | f._bf._base = f._p = (unsigned char *) str; |
---|
615 | f._bf._size = f._w = INT_MAX; |
---|
616 | f._file = -1; /* No file. */ |
---|
617 | va_start (ap, fmt); |
---|
618 | ret = _svfprintf_r (_REENT, &f, fmt, ap); |
---|
619 | va_end (ap); |
---|
620 | *f._p = '\0'; /* terminate the string */ |
---|
621 | return (ret); |
---|
622 | } |
---|
623 | |
---|
624 | #ifdef _NANO_FORMATTED_IO |
---|
625 | int |
---|
626 | siprintf (char *, const char *, ...) |
---|
627 | _ATTRIBUTE ((__alias__("sprintf"))); |
---|
628 | #endif |
---|
629 | #endif |
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