KSTRTOUL(9) Basic C Library Functions KSTRTOUL(9)NAME
kstrtoul - convert a string to an unsigned long
int kstrtoul(const char * s, unsigned int base, unsigned long * res);
The start of the string. The string must be null-terminated, and may also include a single newline before its terminating null. The
first character may also be a plus sign, but not a minus sign.
The number base to use. The maximum supported base is 16. If base is given as 0, then the base of the string is automatically detected
with the conventional semantics - If it begins with 0x the number will be parsed as a hexadecimal (case insensitive), if it otherwise
begins with 0, it will be parsed as an octal number. Otherwise it will be parsed as a decimal.
Where to write the result of the conversion on success.
Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. Used as a replacement for the obsolete simple_strtoull. Return code
must be checked.
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ddi_strtoul(9F) Kernel Functions for Drivers ddi_strtoul(9F)NAME
ddi_strtoul - String conversion functions
int ddi_strtoul(const char *str, char **endptr, int base, unsigned long *result);
Solaris DDI specific (Solaris DDI)
str Pointer to a character string to be converted.
endptr Post-conversion final string of unrecognized characters.
base Radix used for conversion.
result Pointer to variable which contains the converted value.
The ddi_strtoul() function converts the initial portion of the string pointed to by str to a type unsigned long int representation and
stores the converted value in result.
The function first decomposes the input string into three parts:
1. An initial (possibly empty) sequence of white-space characters (' ', ' ', '
2. A subject sequence interpreted as an integer represented in some radix determined by the value of base
3. A final string of one or more unrecognized characters, including the terminating null byte of the input string.
The ddi_strtoul() function then attempts to convert the subject sequence to an unsigned integer and returns 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 con-
stant, any of which may be preceded by a plus ("+") or minus ("-") 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 plus or minus sign. The letters from a (or A) to z (or Z) inclusive are
ascribed the values 10 to 35 and only letters whose ascribed values are less than that of base are permitted. If the value of base is 16,
the characters 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 string, starting with the first non-white-space character
that is of the expected form. The subject sequence contains no characters if the input string is empty or consists entirely of white-space
characters, or if the first non-white-space character 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 characters 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 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 and the value of str is stored in the
object pointed to by endptr, provided that endptr is not a null pointer.
Upon successful completion, ddi_strtoul() returns 0 and stores the converted value in result. If no conversion is performed due to invalid
base, ddi_strtoul() returns EINVAL and the variable pointed by result is not changed.
If the correct value is outside the range of representable values, ddi_strtoul() returns ERANGE and the value pointed to by result is not
The ddi_strtoul() function may be called from user, kernel or interrupt context.
Writing Device Drivers
SunOS 5.10 13 May 2004 ddi_strtoul(9F)