wcstol(3p) — Linux manual page


WCSTOL(3P)                POSIX Programmer's Manual               WCSTOL(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       wcstol, wcstoll — convert a wide-character string to a long integer

SYNOPSIS         top

       #include <wchar.h>

       long wcstol(const wchar_t *restrict nptr, wchar_t **restrict endptr,
           int base);
       long long wcstoll(const wchar_t *restrict nptr,
           wchar_t **restrict endptr, int base);

DESCRIPTION         top

       The functionality described on this reference page is aligned with
       the ISO C standard. Any conflict between the requirements described
       here and the ISO C standard is unintentional. This volume of
       POSIX.1‐2008 defers to the ISO C standard.

       These functions shall convert the initial portion of the wide-
       character string pointed to by nptr to long and long long,
       respectively. First, they shall decompose the input string into three

        1. An initial, possibly empty, sequence of white-space wide-
           character codes (as specified by iswspace())

        2. A subject sequence interpreted as an integer represented in some
           radix determined by the value of base

        3. A final wide-character string of one or more unrecognized wide-
           character codes, including the terminating null wide-character
           code of the input wide-character string

       Then they shall attempt to convert the subject sequence to an
       integer, and return the result.

       If base is 0, the expected form of the subject sequence is that of a
       decimal constant, octal constant, or hexadecimal constant, any of
       which may be preceded by a '+' or '−' sign. A decimal constant begins
       with a non-zero digit, and consists of a sequence of decimal digits.
       An octal constant consists of the prefix '0' optionally followed by a
       sequence of the digits '0' to '7' only. A hexadecimal constant
       consists of the prefix 0x or 0X followed by a sequence of the decimal
       digits and letters 'a' (or 'A') to 'f' (or 'F') with values 10 to 15

       If the value of base is between 2 and 36, the expected form of the
       subject sequence is a sequence of letters and digits representing an
       integer with the radix specified by base, optionally preceded by a
       '+' or '−' sign, but not including an integer suffix. The letters
       from 'a' (or 'A') to 'z' (or 'Z') inclusive are ascribed the values
       10 to 35; only letters whose ascribed values are less than that of
       base shall be permitted. If the value of base is 16, the wide-
       character code representations of 0x or 0X may optionally precede the
       sequence of letters and digits, following the sign if present.

       The subject sequence is defined as the longest initial subsequence of
       the input wide-character string, starting with the first non-white-
       space wide-character code that is of the expected form. The subject
       sequence contains no wide-character codes if the input wide-character
       string is empty or consists entirely of white-space wide-character
       code, or if the first non-white-space wide-character code is other
       than a sign or a permissible letter or digit.

       If the subject sequence has the expected form and base is 0, the
       sequence of wide-character codes starting with the first digit shall
       be interpreted as an integer constant. If the subject sequence has
       the expected form and the value of base is between 2 and 36, it shall
       be used as the base for conversion, ascribing to each letter its
       value as given above. If the subject sequence begins with a minus-
       sign, the value resulting from the conversion shall be negated. A
       pointer to the final wide-character string shall be stored in the
       object pointed to by endptr, provided that endptr is not a null

       In other than the C or POSIX locales, other implementation-defined
       subject sequences may be accepted.

       If the subject sequence is empty or does not have the expected form,
       no conversion shall be performed; the value of nptr shall be stored
       in the object pointed to by endptr, provided that endptr is not a
       null pointer.

       These functions shall not change the setting of errno if successful.

       Since 0, {LONG_MIN} or {LLONG_MIN} and {LONG_MAX} or {LLONG_MAX} are
       returned on error and are also valid returns on success, an
       application wishing to check for error situations should set errno to
       0, then call wcstol() or wcstoll(), then check errno.

RETURN VALUE         top

       Upon successful completion, these functions shall return the
       converted value, if any. If no conversion could be performed, 0 shall
       be returned and errno may be set to indicate the error.  If the
       correct value is outside the range of representable values,
       {LONG_MIN}, {LONG_MAX}, {LLONG_MIN}, or {LLONG_MAX} shall be returned
       (according to the sign of the value), and errno set to [ERANGE].

ERRORS         top

       These functions shall fail if:

       EINVAL The value of base is not supported.

       ERANGE The value to be returned is not representable.

       These functions may fail if:

       EINVAL No conversion could be performed.

       The following sections are informative.

EXAMPLES         top




RATIONALE         top




SEE ALSO         top

       fscanf(3p), iswalpha(3p), wcstod(3p)

       The Base Definitions volume of POSIX.1‐2008, wchar.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                          WCSTOL(3P)

Pages that refer to this page: wchar.h(0p)fwscanf(3p)wcstod(3p)wcstof(3p)wcstoimax(3p)wcstoll(3p)wcstoul(3p)wcstoull(3p)