# kstrtoull(9) [centos man page]

KSTRTOULL(9) Basic C Library Functions KSTRTOULL(9)NAME

kstrtoull - convert a string to an unsigned long longSYNOPSIS

int kstrtoull(const char * s, unsigned int base, unsigned long long * res);ARGUMENTS

s 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. base 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. res Where to write the result of the conversion on success.DESCRIPTION

Returns 0 on success,on overflow and-ERANGEon parsing error. Used as a replacement for the obsolete simple_strtoull. Return code must be checked.-EINVALCOPYRIGHT

Kernel Hackers Manual 3.10June 2014 KSTRTOULL(9)

## Check Out this Related Man Page

STRTOUL(3) Linux Programmer's Manual STRTOUL(3)NAME

strtoul, strtoull, strtouq - convert a string to an unsigned long integerSYNOPSIS

#include <stdlib.h> unsigned long int strtoul(const char *nptr, char **endptr, int base); unsigned long long int strtoull(const char *nptr, char **endptr, int base);DESCRIPTION

The strtoul() function converts the initial part of the string in nptr to an unsigned long integer value according to the given base, which must be between 2 and 36 inclusive, or be the special value 0. The string must begin with an arbitrary amount of white space (as determined by isspace(3)) followed by a single optional `+' or `-' sign. If base is zero or 16, the string may then include a `0x' prefix, and the number will be read in base 16; otherwise, a zero base is taken as 10 (decimal) unless the next character is `0', in which case it is taken as 8 (octal). The remainder of the string is converted to an unsigned long int value in the obvious manner, stopping at the first character which is not a valid digit in the given base. (In bases above 10, the letter `A' in either upper or lower case represents 10, `B' represents 11, and so forth, with `Z' representing 35.) If endptr is not NULL, strtoul() stores the address of the first invalid character in *endptr. If there were no digits at all, strtoul() stores the original value of nptr in *endptr (and returns 0). In particular, if *nptr is not `' but **endptr is `' on return, the entire string is valid. The strtoull() function works just like the strtoul() function but returns an unsigned long long integer value.RETURN VALUE

The strtoul() function returns either the result of the conversion or, if there was a leading minus sign, the negation of the result of the conversion, unless the original (non-negated) value would overflow; in the latter case, strtoul() returns ULONG_MAX and sets the global variable errno to ERANGE. Precisely the same holds for strtoull() (with ULLONG_MAX instead of ULONG_MAX).ERRORS

ERANGE The resulting value was out of range. EINVAL (not in C99) The given base contains an unsupported value. The implementation may also set errno to EINVAL in case no conversion was performed (no digits seen, and 0 returned).NOTES

In locales other than the "C" locale, also other strings may be accepted. (For example, the thousands separator of the current locale may be supported.) BSD also has u_quad_t strtouq(const char *nptr, char **endptr, int base); with completely analogous definition. Depending on the wordsize of the current architecture, this may be equivalent to strtoull() or to strtoul().CONFORMING TO

strtoul() conforms to SVID 3, BSD 4.3, ISO 9899 (C99) and POSIX, and strtoull() to ISO 9899 (C99) and POSIX-2001.SEE ALSO

atof(3), atoi(3), atol(3), strtod(3), strtol(3)GNU

2002-05-30 STRTOUL(3)