wcstol(3S)wcstol(3S)NAME
wcstol, wcstoul, wcstoll, wcstoull - convert wide character string to
long integer, unsigned long integer, long long integer, unsigned long
long integer, respectively
SYNOPSIS
#include <wchar.h>
long wcstol(const wchar_t *nptr, wchar_t **endptr, int base);
unsigned long wcstoul(const wchar_t *nptr, wchar_t **endptr, int base);
long long int wcstoll(const wchar_t *nptr, wchar_t **endptr, int base);
unsigned long long int wcstoull(const wchar_t *nptr, wchar_t **endptr,
int base);
DESCRIPTION (International Functions)
The wcstol, wcstoul, wcstoll, and wcstoull functions convert the initial
portion of the wide character string pointed to by nptr to long int,
unsigned long int, long long int, and unsigned long long int
representation, respectively. First these functions decompose the input
wide character string into three parts: an initial, possibly empty,
sequence of white-space wide-character codes (as specified by iswspace),
a subject sequence interpreted as an integer represented in some radix
determined by the value of base; and a final wide character string of one
or more unrecognised wide character codes, including the terminating null
wide-character code of the input wide character string. Then these
functions 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 respectively.
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 are 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.
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wcstol(3S)wcstol(3S)
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 is interpreted as
an integer constant. If the subject sequence has the expected form and
the value of base is between 2 and 36, it is 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 is negated. A pointer to the final wide character string is
stored in the object pointed to by endptr, provided that endptr is not a
null pointer.
If the subject sequence is empty or does not have the expected form, no
conversion is performed; the value of nptr is stored in the object
pointed to by endptr, provided that endptr is not a null pointer.
RETURN VALUES
Upon successful completion, wcstol, wcstoll, wcstoul, and wcstoull return
the converted value, if any. If no conversion could be performed, 0 is
returned and errno may be set to indicate the error. If the correct
value is outside the range of representable values, {LONG_MAX},
{LONGLONG_MAX}, {ULONG_MAX}, {ULONGLONG_MAX}, {LONG_MIN}, {LONGLONG_MIN},
{ULONG_MIN}, or {ULONGLONG_MIN} is returned (according to the sign of the
value and which version of the routine is called--signed or unsigned),
and errno is set to [ERANGE].
DIAGNOSTICS
wcstol, wcstoll, wcstoul, and wcstoull will fail if:
[EINVAL] The value of base is not supported.
[ERANGE] The value to be returned is not representable.
wcstol, wcstoll, wcstoul, and wcstoull may fail if:
[EINVAL] No conversion could be performed.
APPLICATION USAGE
Because 0, {LONG_MIN}, {LONGLONG_MIN}, {ULONG_MIN}, {ULONGLONG_MIN},
{LONG_MAX}, {LONGLONG_MAX}, {ULONG_MAX}, and {ULONGLONG_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, wcstoll, wcstoul, or wcstoull, then check errno and if it is 0,
assume an error has occurred.
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wcstol(3S)wcstol(3S)SEE ALSOwctype(3S), wcstod(3S), <wchar.h>, <limits.h>.
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