Name
strtoul function — Converts a string to unsigned long
Synopsis
unsigned long strtoul(const char* str, char** end, int base)
The strtoul
function
converts a character array to an unsigned long integer. The string
str
is divided into three parts:
optional whitespace, the text of the integer value, and a trailing
part, which starts with the first character that cannot be part of
an integer. The first part is skipped, and the second part is
converted to an unsigned long integer. If the second part is empty,
0
is returned. If end
is not null, *end
is assigned a pointer to the start of
the third part of str
. If the
third part is empty, *end`
points
to the terminating null character.
If base
is 0
, the base is determined from the prefix
of the integer text: a leading 0x
or 0X
means hexadecimal, a
leading 0
means octal, and
anything else is decimal. Otherwise, base
must be between 2 and 36, in which
the letters a
-z
(of either case) represent digits with
values of 10-35. Only letters that are appropriate for the base are
permitted, that is, the corresponding digit value must be less than
the base.
If the resulting value is too large to fit in an unsigned
long
int
, the value ULONG_MAX
is returned, and errno
is set to ERANGE
.
See Also
atol function, strtod function, strtol function, wcstoul
in <cwchar>
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