watol(3C)
NAME
wcstol, wstol, watol, watoll, watoi - convert wide character
string to long integer
SYNOPSIS
#include <wchar.h>
long int wcstol(const wchar_t *nptr, wchar_t **endptr, int
base);
#include <widec.h>
long int wstol(const wchar_t *nptr, wchar_t **endptr, int
base);
long watol(wchar_t *nptr);
long long watoll(wchar_t *nptr);
int watoi(wchar_t *nptr);
DESCRIPTION
The wcstol() and wstol() functions convert the initial por-
tion of the wide character string pointed to by nptr to long
int representation. They first decompose the input wide
character string into three parts: an initial, possibly
empty, sequence of white-space wide-character codes (as
specified by iswspace(3C)), 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 ter-
minating null wide-character code of the input wide charac-
ter string. They then attempt to convert the subject
sequence to an integer, and return the result.
If the value of 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 fol-
lowed by a sequence of the digits `0' to `7' only. A hexade-
cimal 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 representa-
tions 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 the value
of 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.
In other than the POSIX locale, additional implementation-
dependent subject sequence forms may be accepted.
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.
The watol() function is equivalent to wstol(str, (wchar_t
**)NULL, 10).
The watoll() function is the long-long (double long) version
of watol().
The watoi() function is equivalent to (int)watol().
RETURN VALUES
Upon successful completion, wcstol() and wstol() return the
converted value, if any. If no conversion could be per-
formed, 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} or {LONG_MIN} is returned
(according to the sign of the value), and errno is set to
ERANGE.
ERRORS
The wcstol() and wstol() functions will fail if:
EINVAL
The value of base is not supported.
ERANGE
The value to be returned is not representable.
The wcstol() and wstol() functions may fail if:
EINVAL
No conversion could be performed.
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
SEE ALSO
iswalpha(3C), iswspace(3C), scanf(3C), wcstod(3C), attri-
butes(5)
NOTES
Because 0, {LONG_MIN}, and {LONG_MAX} are returned on error
and are also valid returns on success, an application wish-
ing to check for error situations should set errno to 0,
call wcstol() or wstol(), then check errno and if it is
non-zero assume an error has occurred.
Truncation from long long to long can take place upon
assignment or by an explicit cast.
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