1STRFMON(3P) POSIX Programmer's Manual STRFMON(3P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 strfmon - convert monetary value to a string
13
15 #include <monetary.h>
16 ssize_t strfmon(char *restrict s, size_t maxsize,
18 const char *restrict format, ...);
19
22 The strfmon() function shall place characters into the array pointed to
23 by s as controlled by the string pointed to by format. No more than
24 maxsize bytes are placed into the array.
25 The format is a character string, beginning and ending in its initial
27 state, if any, that contains two types of objects: plain characters,
28 which are simply copied to the output stream, and conversion specifica‐
29 tions, each of which shall result in the fetching of zero or more argu‐
30 ments which are converted and formatted. The results are undefined if
31 there are insufficient arguments for the format. If the format is
32 exhausted while arguments remain, the excess arguments are simply
33 ignored.
34 The application shall ensure that a conversion specification consists
36 of the following sequence:
37 * A '%' character
39 * Optional flags
41 * Optional field width
43 * Optional left precision
45 * Optional right precision
47 * A required conversion specifier character that determines the con‐
49 version to be performed
50 Flags
52 One or more of the following optional flags can be specified to control
53 the conversion:
54 =f An '=' followed by a single character f which is used as the
56 numeric fill character. In order to work with precision or width
57 counts, the fill character shall be a single byte character; if
58 not, the behavior is undefined. The default numeric fill charac‐
59 ter is the <space>. This flag does not affect field width fill‐
60 ing which always uses the <space>. This flag is ignored unless
61 a left precision (see below) is specified.
62 ^ Do not format the currency amount with grouping characters. The
64 default is to insert the grouping characters if defined for the
65 current locale.
66 + or ( Specify the style of representing positive and negative currency
68 amounts. Only one of '+' or '(' may be specified. If '+' is
69 specified, the locale's equivalent of '+' and '-' are used (for
70 example, in the U.S., the empty string if positive and '-' if
71 negative). If '(' is specified, negative amounts are enclosed
72 within parentheses. If neither flag is specified, the '+' style
73 is used.
74 ! Suppress the currency symbol from the output conversion.
76 - Specify the alignment. If this flag is present the result of the
78 conversion is left-justified (padded to the right) rather than
79 right-justified. This flag shall be ignored unless a field width
80 (see below) is specified.
81 Field Width
84 w A decimal digit string w specifying a minimum field width in
85 bytes in which the result of the conversion is right-justified
86 (or left-justified if the flag '-' is specified). The default
87 is 0.
88 Left Precision
91 #n A '#' followed by a decimal digit string n specifying a maximum
92 number of digits expected to be formatted to the left of the
93 radix character. This option can be used to keep the formatted
94 output from multiple calls to the strfmon() function aligned in
95 the same columns. It can also be used to fill unused positions
96 with a special character as in "$***123.45" . This option causes
97 an amount to be formatted as if it has the number of digits
98 specified by n. If more than n digit positions are required,
99 this conversion specification is ignored. Digit positions in
100 excess of those actually required are filled with the numeric
101 fill character (see the =f flag above).
102 If grouping has not been suppressed with the '^' flag, and it is
104 defined for the current locale, grouping separators are inserted before
105 the fill characters (if any) are added. Grouping separators are not
106 applied to fill characters even if the fill character is a digit.
107 To ensure alignment, any characters appearing before or after the num‐
109 ber in the formatted output such as currency or sign symbols are padded
110 as necessary with <space>s to make their positive and negative formats
111 an equal length.
112 Right Precision
115 .p A period followed by a decimal digit string p specifying the
116 number of digits after the radix character. If the value of the
117 right precision p is 0, no radix character appears. If a right
118 precision is not included, a default specified by the current
119 locale is used. The amount being formatted is rounded to the
120 specified number of digits prior to formatting.
121 Conversion Specifier Characters
124 The conversion specifier characters and their meanings are:
125 i The double argument is formatted according to the locale's
127 international currency format (for example, in the U.S.: USD
128 1,234.56). If the argument is ±Inf or NaN, the result of the
129 conversion is unspecified.
130 n The double argument is formatted according to the locale's
132 national currency format (for example, in the U.S.: $1,234.56).
133 If the argument is ±Inf or NaN, the result of the conversion is
134 unspecified.
135 % Convert to a '%' ; no argument is converted. The entire conver‐
137 sion specification shall be %% .
138 Locale Information
141 The LC_MONETARY category of the program's locale affects the behavior
142 of this function including the monetary radix character (which may be
143 different from the numeric radix character affected by the LC_NUMERIC
144 category), the grouping separator, the currency symbols, and formats.
145 The international currency symbol should be conformant with the
146 ISO 4217:1995 standard.
147 If the value of maxsize is greater than {SSIZE_MAX}, the result is
149 implementation-defined.
150
152 If the total number of resulting bytes including the terminating null
153 byte is not more than maxsize, strfmon() shall return the number of
154 bytes placed into the array pointed to by s, not including the termi‐
155 nating null byte. Otherwise, -1 shall be returned, the contents of the
156 array are unspecified, and errno shall be set to indicate the error.
157
159 The strfmon() function shall fail if:
160 E2BIG Conversion stopped due to lack of space in the buffer.
162 The following sections are informative.
165
167 Given a locale for the U.S. and the values 123.45, -123.45, and
168 3456.781, the following output might be produced. Square brackets (
169 "[]" ) are used in this example to delimit the output.
170 %n [$123.45] Default formatting
173 [-$123.45]
174 [$3,456.78]
175 %11n [ $123.45] Right align within an 11-character field
178 [ -$123.45]
179 [ $3,456.78]
180 %#5n [ $ 123.45] Aligned columns for values up to 99999
183 [-$ 123.45]
184 [ $ 3,456.78]
185 %=*#5n [ $***123.45] Specify a fill character
188 [-$***123.45]
189 [ $*3,456.78]
190 %=0#5n [ $000123.45] Fill characters do not use grouping
193 [-$000123.45] even if the fill character is a digit
194 [ $03,456.78]
195 %^#5n [ $ 123.45] Disable the grouping separator
198 [-$ 123.45]
199 [ $ 3456.78]
200 %^#5.0n [ $ 123] Round off to whole units
203 [-$ 123]
204 [ $ 3457]
205 %^#5.4n [ $ 123.4500] Increase the precision
208 [-$ 123.4500]
209 [ $ 3456.7810]
210 %(#5n [$ 123.45] Use an alternative pos/neg style
213 [($ 123.45)]
214 [$ 3,456.78]
215 %!(#5n [ 123.45] Disable the currency symbol
218 [( 123.45)]
219 [ 3,456.78]
220 %-14#5.4n [ $ 123.4500 ] Left-justify the output
223 [-$ 123.4500 ]
224 [ $ 3,456.7810 ]
225 %14#5.4n [ $ 123.4500] Corresponding right-justified output
228 [ -$ 123.4500]
229 [ $ 3,456.7810]
230 See also the EXAMPLES section in fprintf().
232
234 None.
235
237 None.
238
240 Lowercase conversion characters are reserved for future standards use
241 and uppercase for implementation-defined use.
242
244 fprintf(), localeconv(), the Base Definitions volume of
245 IEEE Std 1003.1-2001, <monetary.h>
246
248 Portions of this text are reprinted and reproduced in electronic form
249 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
250 -- Portable Operating System Interface (POSIX), The Open Group Base
251 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
252 Electrical and Electronics Engineers, Inc and The Open Group. In the
253 event of any discrepancy between this version and the original IEEE and
254 The Open Group Standard, the original IEEE and The Open Group Standard
255 is the referee document. The original Standard can be obtained online
256 at http://www.opengroup.org/unix/online.html .
257IEEE/The Open Group 2003 STRFMON(3P)