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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