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

NAME

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

SYNOPSIS

       #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)