1WCSTOUL(3P) POSIX Programmer's Manual WCSTOUL(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
13 wcstoul, wcstoull — convert a wide-character string to an unsigned long
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16 #include <wchar.h>
17 unsigned long wcstoul(const wchar_t *restrict nptr,
19 wchar_t **restrict endptr, int base);
20 unsigned long long wcstoull(const wchar_t *restrict nptr,
21 wchar_t **restrict endptr, int base);
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24 The functionality described on this reference page is aligned with the
25 ISO C standard. Any conflict between the requirements described here
26 and the ISO C standard is unintentional. This volume of POSIX.1‐2008
27 defers to the ISO C standard.
28 The wcstoul() and wcstoull() functions shall convert the initial por‐
30 tion of the wide-character string pointed to by nptr to unsigned long
31 and unsigned long long representation, respectively. First, they shall
32 decompose the input wide-character string into three parts:
33 1. An initial, possibly empty, sequence of white-space wide-character
35 codes (as specified by iswspace())
36 2. A subject sequence interpreted as an integer represented in some
38 radix determined by the value of base
39 3. A final wide-character string of one or more unrecognized wide-
41 character codes, including the terminating null wide-character code
42 of the input wide-character string
43 Then they shall attempt to convert the subject sequence to an unsigned
45 integer, and return the result.
46 If base is 0, the expected form of the subject sequence is that of a
48 decimal constant, octal constant, or hexadecimal constant, any of which
49 may be preceded by a '+' or '−' sign. A decimal constant begins with a
50 non-zero digit, and consists of a sequence of decimal digits. An octal
51 constant consists of the prefix '0' optionally followed by a sequence
52 of the digits '0' to '7' only. A hexadecimal constant consists of the
53 prefix 0x or 0X followed by a sequence of the decimal digits and let‐
54 ters 'a' (or 'A') to 'f' (or 'F') with values 10 to 15 respectively.
55 If the value of base is between 2 and 36, the expected form of the sub‐
57 ject sequence is a sequence of letters and digits representing an inte‐
58 ger with the radix specified by base, optionally preceded by a '+' or
59 '−' sign, but not including an integer suffix. The letters from 'a' (or
60 'A') to 'z' (or 'Z') inclusive are ascribed the values 10 to 35; only
61 letters whose ascribed values are less than that of base shall be per‐
62 mitted. If the value of base is 16, the wide-character codes 0x or 0X
63 may optionally precede the sequence of letters and digits, following
64 the sign if present.
65 The subject sequence is defined as the longest initial subsequence of
67 the input wide-character string, starting with the first wide-character
68 code that is not white space and is of the expected form. The subject
69 sequence contains no wide-character codes if the input wide-character
70 string is empty or consists entirely of white-space wide-character
71 codes, or if the first wide-character code that is not white space is
72 other than a sign or a permissible letter or digit.
73 If the subject sequence has the expected form and base is 0, the
75 sequence of wide-character codes starting with the first digit shall be
76 interpreted as an integer constant. If the subject sequence has the
77 expected form and the value of base is between 2 and 36, it shall be
78 used as the base for conversion, ascribing to each letter its value as
79 given above. If the subject sequence begins with a minus-sign, the
80 value resulting from the conversion shall be negated. A pointer to the
81 final wide-character string shall be stored in the object pointed to by
82 endptr, provided that endptr is not a null pointer.
83 In other than the C or POSIX locales, other implementation-defined sub‐
85 ject sequences may be accepted.
86 If the subject sequence is empty or does not have the expected form, no
88 conversion shall be performed; the value of nptr shall be stored in the
89 object pointed to by endptr, provided that endptr is not a null
90 pointer.
91 These functions shall not change the setting of errno if successful.
93 Since 0, {ULONG_MAX}, and {ULLONG_MAX} are returned on error and 0 is
95 also a valid return on success, an application wishing to check for
96 error situations should set errno to 0, then call wcstoul() or
97 wcstoull(), then check errno.
98
100 Upon successful completion, the wcstoul() and wcstoull() functions
101 shall return the converted value, if any. If no conversion could be
102 performed, 0 shall be returned and errno may be set to indicate the
103 error. If the correct value is outside the range of representable val‐
104 ues, {ULONG_MAX} or {ULLONG_MAX} respectively shall be returned and
105 errno set to [ERANGE].
106
108 These functions shall fail if:
109 EINVAL The value of base is not supported.
111 ERANGE The value to be returned is not representable.
113 These functions may fail if:
115 EINVAL No conversion could be performed.
117 The following sections are informative.
119
121 None.
122
124 None.
125
127 None.
128
130 None.
131
133 fscanf(), iswalpha(), wcstod(), wcstol()
134 The Base Definitions volume of POSIX.1‐2008, <wchar.h>
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138 Portions of this text are reprinted and reproduced in electronic form
139 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
140 -- Portable Operating System Interface (POSIX), The Open Group Base
141 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
142 cal and Electronics Engineers, Inc and The Open Group. (This is
143 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
144 event of any discrepancy between this version and the original IEEE and
145 The Open Group Standard, the original IEEE and The Open Group Standard
146 is the referee document. The original Standard can be obtained online
147 at http://www.unix.org/online.html .
148 Any typographical or formatting errors that appear in this page are
150 most likely to have been introduced during the conversion of the source
151 files to man page format. To report such errors, see https://www.ker‐
152 nel.org/doc/man-pages/reporting_bugs.html .
153IEEE/The Open Group 2013 WCSTOUL(3P)