1WCSTOL(3P) POSIX Programmer's Manual WCSTOL(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 wcstol, wcstoll — convert a wide-character string to a long integer
13
15 #include <wchar.h>
16 long wcstol(const wchar_t *restrict nptr, wchar_t **restrict endptr,
18 int base);
19 long long wcstoll(const wchar_t *restrict nptr,
20 wchar_t **restrict endptr, int base);
21
23 The functionality described on this reference page is aligned with the
24 ISO C standard. Any conflict between the requirements described here
25 and the ISO C standard is unintentional. This volume of POSIX.1‐2017
26 defers to the ISO C standard.
27 These functions shall convert the initial portion of the wide-character
29 string pointed to by nptr to long and long long, respectively. First,
30 they shall decompose the input string into three parts:
31 1. An initial, possibly empty, sequence of white-space wide-character
33 codes (as specified by iswspace())
34 2. A subject sequence interpreted as an integer represented in some
36 radix determined by the value of base
37 3. A final wide-character string of one or more unrecognized wide-
39 character codes, including the terminating null wide-character code
40 of the input wide-character string
41 Then they shall attempt to convert the subject sequence to an integer,
43 and return the result.
44 If base is 0, the expected form of the subject sequence is that of a
46 decimal constant, octal constant, or hexadecimal constant, any of which
47 may be preceded by a '+' or '-' sign. A decimal constant begins with a
48 non-zero digit, and consists of a sequence of decimal digits. An octal
49 constant consists of the prefix '0' optionally followed by a sequence
50 of the digits '0' to '7' only. A hexadecimal constant consists of the
51 prefix 0x or 0X followed by a sequence of the decimal digits and let‐
52 ters 'a' (or 'A') to 'f' (or 'F') with values 10 to 15 respectively.
53 If the value of base is between 2 and 36, the expected form of the sub‐
55 ject sequence is a sequence of letters and digits representing an inte‐
56 ger with the radix specified by base, optionally preceded by a '+' or
57 '-' sign, but not including an integer suffix. The letters from 'a' (or
58 'A') to 'z' (or 'Z') inclusive are ascribed the values 10 to 35; only
59 letters whose ascribed values are less than that of base shall be per‐
60 mitted. If the value of base is 16, the wide-character code representa‐
61 tions of 0x or 0X may optionally precede the sequence of letters and
62 digits, following the sign if present.
63 The subject sequence is defined as the longest initial subsequence of
65 the input wide-character string, starting with the first non-white-
66 space wide-character code that is of the expected form. The subject
67 sequence contains no wide-character codes if the input wide-character
68 string is empty or consists entirely of white-space wide-character
69 code, or if the first non-white-space wide-character code is other than
70 a sign or a permissible letter or digit.
71 If the subject sequence has the expected form and base is 0, the
73 sequence of wide-character codes starting with the first digit shall be
74 interpreted as an integer constant. If the subject sequence has the
75 expected form and the value of base is between 2 and 36, it shall be
76 used as the base for conversion, ascribing to each letter its value as
77 given above. If the subject sequence begins with a <hyphen-minus>, the
78 value resulting from the conversion shall be negated. A pointer to the
79 final wide-character string shall be stored in the object pointed to by
80 endptr, provided that endptr is not a null pointer.
81 In other than the C or POSIX locale, additional locale-specific subject
83 sequence forms may be accepted.
84 If the subject sequence is empty or does not have the expected form, no
86 conversion shall be performed; the value of nptr shall be stored in the
87 object pointed to by endptr, provided that endptr is not a null
88 pointer.
89 These functions shall not change the setting of errno if successful.
91 Since 0, {LONG_MIN} or {LLONG_MIN} and {LONG_MAX} or {LLONG_MAX} are
93 returned on error and are also valid returns on success, an application
94 wishing to check for error situations should set errno to 0, then call
95 wcstol() or wcstoll(), then check errno.
96
98 Upon successful completion, these functions shall return the converted
99 value, if any. If no conversion could be performed, 0 shall be returned
100 and errno may be set to indicate the error. If the correct value is
101 outside the range of representable values, {LONG_MIN}, {LONG_MAX},
102 {LLONG_MIN}, or {LLONG_MAX} shall be returned (according to the sign of
103 the value), and errno set to [ERANGE].
104
106 These functions shall fail if:
107 EINVAL The value of base is not supported.
109 ERANGE The value to be returned is not representable.
111 These functions may fail if:
113 EINVAL No conversion could be performed.
115 The following sections are informative.
117
119 None.
120
122 None.
123
125 None.
126
128 None.
129
131 fscanf(), iswalpha(), wcstod()
132 The Base Definitions volume of POSIX.1‐2017, <wchar.h>
134
136 Portions of this text are reprinted and reproduced in electronic form
137 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
138 table Operating System Interface (POSIX), The Open Group Base Specifi‐
139 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
140 Electrical and Electronics Engineers, Inc and The Open Group. In the
141 event of any discrepancy between this version and the original IEEE and
142 The Open Group Standard, the original IEEE and The Open Group Standard
143 is the referee document. The original Standard can be obtained online
144 at http://www.opengroup.org/unix/online.html .
145 Any typographical or formatting errors that appear in this page are
147 most likely to have been introduced during the conversion of the source
148 files to man page format. To report such errors, see https://www.ker‐
149 nel.org/doc/man-pages/reporting_bugs.html .
150IEEE/The Open Group 2017 WCSTOL(3P)